Optical fiber waveguide in an endoscopic system for laser mapping imaging

ABSTRACT

Optical fiber waveguide for communicating electromagnetic radiation pulsed by an emitter in an endoscopic imaging system. A system includes an emitter for emitting pulses of electromagnetic radiation and an endoscope comprising an image sensor for sensing reflected electromagnetic radiation. The system includes a waveguide communicating the pulses of electromagnetic radiation from the emitter to the endoscope. The system is such that at least a portion of the pulses of electromagnetic radiation emitted by the emitter comprises a laser mapping pattern.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 62/864,281, filed Jun. 20, 2019, titled “SYSTEMS,METHODS, AND DEVICES FOR PROVIDING ILLUMINATION IN AN ENDOSCOPICHYPERSPECTRAL AND FLUORESCENCE IMAGING ENVIRONMENT,” which isincorporated herein by reference in its entirety, including but notlimited to those portions that specifically appear hereinafter, theincorporation by reference being made with the following exception: Inthe event that any portion of the above-referenced provisionalapplication is inconsistent with this application, this applicationsupersedes the above-referenced provisional application.

TECHNICAL FIELD

This disclosure is directed to digital imaging and is particularlydirected to laser mapping imaging in a light deficient environment.

BACKGROUND

Advances in technology have provided advances in imaging capabilitiesfor medical use. An endoscope may be used to look inside a body andexamine the interior of an organ or cavity of the body. Endoscopes areused for investigating a patient's symptoms, confirming a diagnosis, orproviding medical treatment. A medical endoscope may be used for viewinga variety of body systems and parts such as the gastrointestinal tract,the respiratory tract, the urinary tract, the abdominal cavity, and soforth. Endoscopes may further be used for surgical procedures such asplastic surgery procedures, procedures performed on joints or bones,procedures performed on the neurological system, procedures performedwithin the abdominal cavity, and so forth.

In some instances of endoscopic imaging, it may be beneficial ornecessary to view a space in color. A digital color image includes atleast three layers, or “color channels,” that cumulatively form an imagewith a range of hues. Each of the color channels measures the intensityand chrominance of light for a spectral band. Commonly, a digital colorimage includes a color channel for red, green, and blue spectral bandsof light (this may be referred to as a Red Green Blue or RGB image).Each of the red, green, and blue color channels include brightnessinformation for the red, green, or blue spectral band of light. Thebrightness information for the separate red, green, and blue layers arecombined to create the color image. Because a color image is made up ofseparate layers, a conventional digital camera image sensor includes acolor filter array that permits red, green, and blue visible lightwavelengths to hit selected pixel sensors. Each individual pixel sensorelement is made sensitive to red, green, or blue wavelengths and willonly return image data for that wavelength. The image data from thetotal array of pixel sensors is combined to generate the RGB image. Theat least three distinct types of pixel sensors consume significantphysical space such that the complete pixel array cannot fit in thesmall distal end of an endoscope.

Because a traditional image sensor cannot fit in the distal end of anendoscope, the image sensor is traditionally located in a handpiece unitof an endoscope that is held by an endoscope operator and is not placedwithin the body cavity. In such an endoscope, light is transmitted alongthe length of the endoscope from the handpiece unit to the distal end ofthe endoscope. This configuration has significant limitations.Endoscopes with this configuration are delicate and can be easilymisaligned or damaged when bumped or impacted during regular use. Thiscan significantly degrade the quality of the images and necessitate thatthe endoscope be frequently repaired or replaced.

The traditional endoscope with the image sensor placed in the handpieceunit is further limited to capturing only color images. However, in someimplementations, it may be desirable to capture images with lasermapping image data in addition to color image data. Laser mappingimaging can capture the surface shape of objects and landscapes andmeasure distances between objects within a scene. In someimplementations, it may be desirable to measure distances and surfaceshapes within a body cavity during an endoscopic imaging procedure.

However, applications of laser mapping technology known in the arttypically require highly specialized equipment that may not be usefulfor multiple applications. Further, laser mapping technology provides alimited view of an environment and typically must be used in conjunctionwith multiple separate systems. In the context of endoscopic medicalimaging procedures, all sensors must fit within a small physical areawithin a body cavity. In some instances, the geographic area isexceptionally small and may only accommodate a very small tip of anendoscope. As such, medical endoscopes known in the art are necessarilysmall and cannot accommodate multiple distinct imaging and rangingsystems. It is therefore desirable to develop an endoscopic imagingsystem that is capable of generating laser mapping data in a small spacesuch as a body cavity.

In light of the foregoing, described herein are systems, methods, anddevices for laser mapping imaging in a light deficient environment. Suchsystems, methods, and devices may provide multiple datasets foridentifying critical structures in a body and providing precise andvaluable information about a body cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive implementations of the disclosure aredescribed with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified. Advantages of the disclosure will becomebetter understood with regard to the following description andaccompanying drawings where:

FIG. 1 is a schematic view of a system for digital imaging in a lightdeficient environment with a paired emitter module and pixel array;

FIG. 2 illustrates a system for providing illumination to a lightdeficient environment for endoscopic imaging;

FIG. 2A is a schematic diagram of complementary system hardware;

FIGS. 3A to 3D are illustrations of the operational cycles of a sensorused to construct an exposure frame;

FIG. 4A is a graphical representation of the operation of an embodimentof an electromagnetic emitter;

FIG. 4B is a graphical representation of varying the duration andmagnitude of the emitted electromagnetic pulse to provide exposurecontrol;

FIG. 5 is a graphical representation of an embodiment of the disclosurecombining the operational cycles of a sensor, the electromagneticemitter, and the emitted electromagnetic pulses of FIGS. 3A-4B, whichdemonstrate the imaging system during operation;

FIG. 6A is a schematic diagram of a process for recording a video withfull spectrum light over a period of time from t(0) to t(1);

FIG. 6B is a schematic diagram of a process for recording a video bypulsing portioned spectrum light over a period of time from t(0) tot(1);

FIGS. 7A-7E illustrate schematic views of the processes over an intervalof time for recording a frame of video for both full spectrum light andpartitioned spectrum light;

FIG. 8 is a graphical display of the delay or jitter between a controlsignal and an emission of electromagnetic radiation by an emitter;

FIG. 9 is a cross-sectional view of an optical fiber bundle comprising acenter fiber and a plurality of surrounding fibers;

FIG. 10 is a graphical display of a top hat profile and a Gaussianprofile for sending electromagnetic radiation to an optical fiberbundle;

FIG. 11 is a side view illustrating the output of electromagneticradiation (light) from an optical fiber bundle in comparison to thefield of view of a camera;

FIG. 12 is a side view illustrating the output of electromagneticradiation from an optical fiber bundle wherein the ends of individualfibers are aimed to provide more uniform distribution of theelectromagnetic radiation;

FIG. 13 is a side view illustrating the output of electromagneticradiation from an optical fiber bundle, wherein the optical fiber bundlecomprises plastic fibers and glass fibers coupled near the output;

FIG. 14 is a side view illustrating the output of electromagneticradiation from an optical fiber bundle comprising a diffuser locatednear the output;

FIG. 15 is a system for providing illumination to a light deficientenvironment for endoscopic imaging;

FIG. 16 is a system for providing illumination to a light deficientenvironment for endoscopic imaging;

FIG. 17A is a perspective view of a portion of an endoscope lumencomprising an inner cavity for receiving optical components and aperipheral cavity for receiving a waveguide;

FIG. 17B is a straight-on view of a portion of an endoscope lumencomprising an inner cavity for receiving optical components including animage sensor and a peripheral cavity for receiving a waveguide;

FIG. 18 is a perspective view of a portion of an endoscope lumen with aplurality of optical fibers disposed within the peripheral cavity andterminating at a distal end of the endoscope lumen;

FIGS. 19A-19C illustrate an emitter module having a plurality ofemitters;

FIG. 20 illustrates a single optical fiber outputting via a diffuser atan output to illuminate a scene in a light deficient environment;

FIG. 21 illustrates a portion of the electromagnetic spectrum dividedinto a plurality of different sub-spectrums which may be emitted byemitters of an emitter module in accordance with the principles andteachings of the disclosure;

FIG. 22 is a schematic diagram illustrating a timing sequence foremission and readout for generating an image frame comprising aplurality of exposure frames resulting from differing partitions ofpulsed light;

FIG. 23 illustrates an imaging system including a single cut filter forfiltering wavelengths of electromagnetic radiation;

FIG. 24 illustrates an imaging system comprising a multiple cut filterfor filtering wavelengths of electromagnetic radiation;

FIG. 25 illustrates an example laser mapping pattern that may be pulsedby an imaging system;

FIGS. 26A and 26B illustrate an implementation having a plurality ofpixel arrays for producing a three-dimensional image in accordance withthe principles and teachings of the disclosure;

FIGS. 27A and 27B illustrate a perspective view and a side view,respectively, of an implementation of an imaging sensor built on aplurality of substrates, wherein a plurality of pixel columns formingthe pixel array are located on the first substrate and a plurality ofcircuit columns are located on a second substrate and showing anelectrical connection and communication between one column of pixels toits associated or corresponding column of circuitry; and

FIGS. 28A and 28B illustrate a perspective view and a side view,respectively, of an implementation of an imaging sensor having aplurality of pixel arrays for producing a three-dimensional image,wherein the plurality of pixel arrays and the image sensor are built ona plurality of substrates.

DETAILED DESCRIPTION

Disclosed herein are systems, methods, and devices for digital imagingthat may be primarily suited to medical applications such as medicalendoscopic imaging. An embodiment of the disclosure is an endoscopicsystem for laser mapping and color imaging in a light deficientenvironment. Such methods, systems, and computer-based productsdisclosed herein provide imaging or diagnostic capabilities for use inmedical robotics applications, such as the use of robotics forperforming imaging procedures, surgical procedures, and the like.

An embodiment of the disclosure is an endoscopic imaging systemcomprising an emitter for emitting pulses of electromagnetic radiationto illuminate a scene. In an embodiment, the emitter is an emittermodule comprising one or more individual emitters for pulsing theelectromagnetic radiation. In an embodiment, the emitter modulecomprises multiple emitters that can operate independently of oneanother and emit different wavelengths of electromagnetic radiation.Each of the multiple emitters may include a bundle of lasers foremitting electromagnetic radiation. The multiple emitters making up theemitter module may each be configured to pulse electromagnetic radiationat different partitions or wavelengths of the electromagnetic spectrum.The pulses of electromagnetic radiation may be pulsed to a waveguide,and the waveguide may then carry the pulsed electromagnetic radiation toa distal end of an endoscope to illuminate the scene. The waveguide mayinclude a single optical fiber or an optical fiber bundle comprising aplurality of optical fibers. The waveguide may include plastic and/orglass optical fibers for communicating electromagnetic radiation fromthe emitter module to the distal end of the endoscope.

In an embodiment, the waveguide terminates at the distal end of theendoscope to emanate a light cone of electromagnetic radiation. Thelight cone defines an area that is illuminated by the pulses ofelectromagnetic radiation. In some instances, the area of the light coneresulting from a single optical fiber or a bundle of optical fibers isinsufficient for effective imaging. In some instances, the resultinglight cone has an area smaller than the visibility region of the imagesensor. Therefore, there is a desire to increase the area of theresulting light cone of electromagnetic radiation that emanates from thewaveguide. In light of the foregoing, disclosed herein are multipleembodiments of a waveguide for increasing the resulting light cone ofillumination at the distal end of the endoscope.

Conventional endoscopes are designed such that the image sensor isplaced at a proximal end of the device within a handpiece unit. Thisconfiguration requires that incident light travel the length of theendoscope by way of precisely coupled optical elements. The preciseoptical elements can easily be misaligned during regular use, and thiscan lead to image distortion or image loss. Embodiments of thedisclosure place an image sensor within the highly space-constrainedenvironment in the distal end of the endoscope itself. This providesgreater optical simplicity when compared with implementations known inthe art. However, an acceptable solution to this approach is by no meanstrivial and introduces its own set of engineering challenges.

There can be a noticeable loss to image quality when the overall size ofan image sensor is minimized such that the image sensor can fit withinthe distal tip of an endoscope. The area of the pixel array of the imagesensor can be reduced by reducing the number of pixels and/or thesensing area of each individual pixel. Each of these modificationsimpacts the resolution, sensitivity, and dynamic range of the resultantimages. Traditional endoscopic imaging systems are geared toward sensingsteady broadband illumination and providing color information by virtueof segmented pixel arrays such as the Bayer pattern array. In light ofthe deficiencies associated with segmented pixel arrays, disclosedherein are alternative systems and methods that use a monochromatic (maybe referred to as “color agnostic”) pixel array that does not includeindividual pixel filters. In the embodiments disclosed herein, the colorinformation is provided by pulsing an emitter with different wavelengthsof electromagnetic radiation. The pulsed imaging system disclosed hereincan generate color images with laser mapping imaging data overlaidthereon.

In an embodiment, the color information is determined by capturingindependent exposure frames in response to pulses of differentwavelengths of electromagnetic radiation. The alternative pulses mayinclude red, green, and blue wavelengths for generating an RGB imageframe consisting of a red exposure frame, a green exposure frame, and ablue exposure frame. In an alternative implementation, the alternativepulses may include luminance (“Y”), red chrominance (“Cr”), and bluechrominance “(Cb”) pulses of light for generating a YCbCr image frameconsisting of luminance data, red chrominance data, and blue chrominancedata. The color image frame may further include data from a lasermapping exposure frame overlaid on the RGB or YCbCr image frame. Thelaser mapping pulse may include one or more pulses for measuringdistances or dimensions within a scene, tracking the presence andlocation of tools in the scene, generating a three-dimensionaltopographical map of the scene, and so forth. Alternating thewavelengths of the pulsed electromagnetic radiation allows the fullpixel array to be exploited and avoids the artifacts introduced by Bayerpattern pixel arrays.

In some instances, it is desirable to generate endoscopic imaging withmultiple data types or multiple images overlaid on one another. Forexample, it may be desirable to generate a color (RGB or YCbCr) imagethat further includes laser mapping imaging data overlaid on the colorimage. An overlaid image of this nature may enable a medicalpractitioner or computer program to identify dimensions and topologiesof a scene based on the laser mapping data. The laser mapping data maybe overlaid on a color image with words, numerals, a topographical map,and so forth. Historically, this would require the use of multiplesensor systems including an image sensor for color imaging and one ormore additional image sensors for laser mapping imaging. In suchsystems, the multiple image sensors would have multiple types of pixelsensors that are each sensitive to distinct ranges of electromagneticradiation. In systems known in the art, this includes the three separatetypes of pixel sensors for generating color image along with additionalpixel sensors for generating the laser mapping image data at differentwavelengths of the electromagnetic spectrum. These multiple differentpixel sensors consume a prohibitively large physical space and cannot belocated at a distal tip of the endoscope. In systems known in the art,the camera or cameras are not placed at the distal tip of the endoscopeand are instead placed in an endoscope handpiece or robotic unit. Thisintroduces numerous disadvantages and causes the endoscope to be verydelicate. The delicate endoscope may be damaged and image quality may bedegraded when the endoscope is bumped or impacted during use.Considering the foregoing, disclosed herein are systems, methods, anddevices for endoscopic imaging in a light deficient environment. Thesystems, methods, and devices disclosed herein provide means foremploying multiple imaging techniques in a single imaging session whilepermitting one or more image sensors to be disposed in a distal tip ofthe endoscope.

Laser Mapping Imaging

In an embodiment, the systems, methods, and devices disclosed hereinprovide means for generating laser mapping data with an endoscopicimaging system. Laser mapping data can be used to determine precisemeasurements and topographical outlines of a scene. In oneimplementation, laser mapping data is used to determine precisemeasurements between, for example, structures or organs in a bodycavity, devices or tools in the body cavity, and/or critical structuresin the body cavity. As discussed herein, the term “laser mapping” mayencompass technologies referred to as laser mapping, laser scanning,topographical scanning, three-dimensional scanning, laser tracking, tooltracking, and others. A laser mapping exposure frame as discussed hereinmay include topographical data for a scene, dimensions between objectsor structures within a scene, dimensions or distances for tools orobjects within a scene, and so forth.

Laser mapping generally includes the controlled deflection of laserbeams. Within the field of three-dimensional object scanning, lasermapping combines controlled steering of laser beams with a laserrangefinder. By taking a distance measurement at every direction, thelaser rangefinder can rapidly capture the surface shape of objects,tools, and landscapes. Construction of a full three-dimensional topologymay include combining multiple surface models that are obtained fromdifferent viewing angles. Various measurement systems and methods existin the art for applications in archaeology, geography, atmosphericphysics, autonomous vehicles, and others. One such system includes lightdetection and ranging (LIDAR), which is a three-dimensional lasermapping system. LIDAR has been applied in navigation systems such asairplanes or satellites to determine position and orientation of asensor in combination with other systems and sensors. LIDAR uses activesensors to illuminate an object and detect energy that is reflected offthe object and back to a sensor.

As discussed herein, the term “laser mapping” includes laser tracking.Laser tracking, or the use of lasers for tool tracking, measures objectsby determining the positions of optical targets held against thoseobjects. Laser trackers can be accurate to the order of 0.025 mm over adistance of several meters. In an embodiment, an endoscopic imagingsystem pulses light for use in conjunction with a laser tracking systemsuch that the position or tools within a scene can be tracked andmeasured. In such an embodiment, the endoscopic imaging system may pulsea laser tracking pattern on a tool, object, or other structure within ascene being imaged by the endoscopic imaging system. A target may beplaced on the tool, object, or other structure within the scene.Measurements between the endoscopic imaging system and the target can betriggered and taken at selected points such that the position of thetarget (and the tool, object, or other structure to which the target isaffixed) can be tracked by the endoscopic imaging system.

Pulsed Imaging

Some implementations of the disclosure include aspects of a combinedsensor and system design that allows for high definition imaging withreduced pixel counts in a controlled illumination environment. This isaccomplished with frame-by-frame pulsing of a single-color wavelengthand switching or alternating each frame between a single, differentcolor wavelength using a controlled light source in conjunction withhigh frame capture rates and a specially designed correspondingmonochromatic sensor. Additionally, electromagnetic radiation outsidethe visible light spectrum may be pulsed to enable the generation of ahyperspectral image. The pixels may be color agnostic such that eachpixel generates data for each pulse of electromagnetic radiation,including pulses for red, green, and blue visible light wavelengthsalong with other wavelengths used for hyperspectral imaging.

A system of the disclosure is an endoscopic imaging system for use in alight deficient environment. The system includes an endoscope comprisingan image sensor, wherein the image sensor is configured to sensereflected electromagnetic radiation for generating a plurality ofexposure frames that can be combined to generate an RGB image frame withhyperspectral data overlaid thereon. The system includes an emitter foremitting pulses of electromagnetic radiation. The system includes acontroller (may alternatively be referred to as a “control circuit” inelectronic communication with the image sensor and the emitter. Thecontroller controls a duty cycle of the emitter in response to signalscorresponding to a duty cycle of the emitter. The image sensor includesbidirectional pads that can send and receive information. Thebidirectional pads of the image sensor operate in a frame period dividedinto three defined states, including a rolling readout state, a serviceline state, and a configuration state. The system includes an oscillatordisposed in the controller and a frequency detector connected to thecontroller. The frequency detector controls a clock frequency of theimage sensor in response to signals from the controller that correspondto the frequency of the oscillator. The system is such that clock signaldata is transmitted from the bidirectional pads of the image sensor tothe controller during the service line phase and the configurationphase. The system is such that exposure frames are synchronized withoutthe use of an input clock or a data transmission clock.

For the purposes of promoting an understanding of the principles inaccordance with the disclosure, reference will now be made to theembodiments illustrated in the drawings and specific language will beused to describe the same. It will nevertheless be understood that nolimitation of the scope of the disclosure is thereby intended. Anyalterations and further modifications of the inventive featuresillustrated herein, and any additional applications of the principles ofthe disclosure as illustrated herein, which would normally occur to oneskilled in the relevant art and having possession of this disclosure,are to be considered within the scope of the disclosure claimed.

Before the structure, systems and methods for producing an image in alight deficient environment are disclosed and described, it is to beunderstood that this disclosure is not limited to the particularstructures, configurations, process steps, and materials disclosedherein as such structures, configurations, process steps, and materialsmay vary somewhat. It is also to be understood that the terminologyemployed herein is used for the purpose of describing particularembodiments only and is not intended to be limiting since the scope ofthe disclosure will be limited only by the appended claims andequivalents thereof.

In describing and claiming the subject matter of the disclosure, thefollowing terminology will be used in accordance with the definitionsset out below.

It must be noted that, as used in this specification and the appendedclaims, the singular forms “a,” “an,” and “the” include plural referentsunless the context clearly dictates otherwise.

As used herein, the terms “comprising,” “including,” “containing,”“characterized by,” and grammatical equivalents thereof are inclusive oropen-ended terms that do not exclude additional, unrecited elements ormethod steps.

As used herein, the phrase “consisting of” and grammatical equivalentsthereof exclude any element or step not specified in the claim.

As used herein, the phrase “consisting essentially of” and grammaticalequivalents thereof limit the scope of a claim to the specifiedmaterials or steps and those that do not materially affect the basic andnovel characteristic or characteristics of the claimed disclosure.

As used herein, the term “proximal” shall refer broadly to the conceptof a portion nearest an origin.

As used herein, the term “distal” shall generally refer to the oppositeof proximal, and thus to the concept of a portion farther from anorigin, or a furthest portion, depending upon the context.

As used herein, color sensors or multi spectrum sensors are thosesensors known to have a color filter array (CFA) thereon to filter theincoming electromagnetic radiation into its separate components. In thevisual range of the electromagnetic spectrum, such a CFA may be built ona Bayer pattern or modification thereon to separate green, red and bluespectrum components of the light.

As used herein, monochromatic sensor refers to an unfiltered imagingsensor. Since the pixels are color agnostic, the effective spatialresolution is appreciably higher than for their color (typicallyBayer-pattern filtered) counterparts in conventional single-sensorcameras. Monochromatic sensors may also have higher quantum efficiencybecause fewer incident photons are wasted between individual pixels.

As used herein, an emitter is a device that is capable of generating andemitting electromagnetic pulses. Various embodiments of emitters may beconfigured to emit pulses and have very specific frequencies or rangesof frequencies from within the entire electromagnetic spectrum. Pulsesmay comprise wavelengths from the visible and non-visible ranges. Anemitter may be cycled on and off to produce a pulse or may produce apulse with a shutter mechanism. An emitter may have variable poweroutput levels or may be controlled with a secondary device such as anaperture or filter. An emitter may emit broad spectrum or full spectrumelectromagnetic radiation that may produce pulses through colorfiltering or shuttering. An emitter may comprise a plurality ofelectromagnetic sources that act individually or in concert. An emittermay comprise an emitter module comprising one or more electromagneticsources for pulsing electromagnetic radiation.

It should be noted that as used herein the term “light” is both aparticle and a wavelength and is intended to denote electromagneticradiation that is detectable by a pixel array 122 and may includewavelengths from the visible and non-visible spectrums ofelectromagnetic radiation. The term “partition” is used herein to mean apre-determined range of wavelengths of the electromagnetic spectrum thatis less than the entire spectrum, or in other words, wavelengths thatmake up some portion of the electromagnetic spectrum. As used herein, anemitter is a light source that may be controllable as to the portion ofthe electromagnetic spectrum that is emitted or that may operate as tothe physics of its components, the intensity of the emissions, or theduration of the emission, or all the above. An emitter may emit light inany dithered, diffused, or collimated emission and may be controlleddigitally or through analog methods or systems. As used herein, anelectromagnetic emitter is a source of a burst of electromagnetic energyand includes light sources, such as lasers, LEDs, incandescent light, orany light source that can be digitally controlled.

Referring now to the figures, FIG. 1 illustrates a schematic diagram ofa system 100 for sequential pulsed imaging in a light deficientenvironment. The system 100 can be deployed to generate an RGB imagewith laser mapping data overlaid on the RGB image. The system 100includes an emitter 102 and a pixel array 122. The emitter 102 pulses apartition of electromagnetic radiation in the light deficientenvironment 112 and the pixel array 122 senses instances of reflectedelectromagnetic radiation. The emitter 102 and the pixel array 122 workin sequence such that one or more pulses of a partition ofelectromagnetic radiation results in image data sensed by the pixelarray 122.

The emitter 102 may include one or more emitters for pulsingelectromagnetic radiation. Each of the one or more emitters may includeone or more lasers for pulsing a partition of wavelengths ofelectromagnetic radiation. The emitter 102 may be capable of pulsingdifferent partitions of the electromagnetic spectrum by way of multipleindependent emitters. As discussed herein, including in the appendedclaims, the term “emitter” may refer to a single emitter or laser forpulsing electromagnetic radiation, a collection of emitters or lasersfor pulsing electromagnetic radiation, and an “emitter module” asdiscussed herein. Therefore, the term “emitter” as used herein shouldnot be seen as limiting and may refer to one or more emitters forpulsing electromagnetic radiation and may also refer to the collectionof emitters found within an emitter module.

A pixel array 122 of an image sensor may be paired with the emitter 102electronically, such that the emitter 102 and the pixel array 122 aresynced during operation for both receiving the emissions and for theadjustments made within the system. The emitter 102 may be tuned to emitelectromagnetic radiation in the form of a laser, which may be pulsed toilluminate a light deficient environment 112. The emitter 102 may pulseat an interval that corresponds to the operation and functionality ofthe pixel array 122. The emitter 102 may pulse light in a plurality ofelectromagnetic partitions such that the pixel array receiveselectromagnetic energy and produces a dataset that corresponds in timewith each specific electromagnetic partition. For example, FIG. 1illustrates an implementation wherein the emitter 102 emits fourdifferent partitions of electromagnetic radiation, including red 104,green 106, blue 108 wavelengths, and a laser mapping 110 pulsing scheme.The laser mapping 110 pulsing scheme may include a grid pattern foridentifying a topology 120 of a scene in the light deficient environment112 and further for measuring dimensions and distances within the scene.The laser mapping 110 pulsing scheme is any suitable pulsing scheme orpattern that may be used for generating laser mapping image data. Thelaser mapping imaging data includes data generated by technologies knownas laser mapping, laser scanning, topographical scanning,three-dimensional scanning, laser tracking, tool tracking, and others.

In an alternative embodiment not illustrated in FIG. 1, the pulsedemissions of light include a luminance (“Y”) emission, a red chrominance(“Cr”) emission, and a blue chrominance (“Cb”) emission in place of thepulsed red 104, pulsed green 106, and pulsed blue 108 emissions. In anembodiment, the controller or the emitter 102 modules the pulses ofelectromagnetic radiation to provide luminance and/or chrominanceinformation according to color transformation coefficients that convertlight energy from red, green, and blue light energy spaces to luminance,red chrominance, and blue chrominance light energy space. The pulsedemissions of light may further include modulated blue chrominance(“λY+Cb”) pulses and/or modulated red chrominance (“δY+Cr”) pulses.

The light deficient environment 112 includes structures, tissues, andother elements that reflect a combination of red 114, green 116, and/orblue 118 light. A structure that is perceived as being red 114 willreflect back pulsed red 104 light. The reflection off the red structureresults in sensed red 105 by the pixel array 122 following the pulsedred 104 emission. The data sensed by the pixel array 122 results in ared exposure frame. A structure that is perceived as being green 116will reflect back pulsed green 106 light. The reflection off the greenstructure results in sensed green 107 by the pixel array 122 followingthe pulsed green 106 emission. The data sensed by the pixel array 122results in a green exposure frame. A structure that is perceived asbeing blue 118 will reflect back pulsed blue 108 light. The reflectionoff the blue structure results in sensed blue 109 by the pixel array 122following the pulsed blue 108 emission. The data sensed by the pixelarray 122 results in a blue exposure frame.

When a structure is a combination of colors, the structure will reflectback a combination of the pulsed red 104, pulsed green 106, and/orpulsed blue 108 emissions. For example, a structure that is perceived asbeing purple will reflect back light from the pulsed red 104 and pulsedblue 108 emissions. The resulting data sensed by the pixel array 122will indicate that light was reflected in the same region following thepulsed red 104 and pulsed blue 108 emissions. When the resultant redexposure frame and blue exposure frames are combined to form the RGBimage frame, the RGB image frame will indicate that the structure ispurple.

In an embodiment where the light deficient environment 112 includes afluorescent reagent or dye or includes one or more fluorescentstructures, tissues, or other elements, the pulsing scheme may includethe emission of a certain fluorescence excitation wavelength. Thecertain fluorescence excitation wavelength may be selected to fluorescea known fluorescent reagent, dye, or other structure. The fluorescentstructure will be sensitive to the fluorescence excitation wavelengthand will emit a fluorescence relaxation wavelength. The fluorescencerelaxation wavelength will be sensed by the pixel array 122 followingthe emission of the fluorescence excitation wavelength. The data sensedby the pixel array 122 results in a fluorescence exposure frame. Thefluorescence exposure frame may be combined with multiple other exposureframes to form an image frame. The data in the fluorescence exposureframe may be overlaid on an RGB image frame that includes data from ared exposure frame, a green exposure frame, and a blue exposure frame.

In an embodiment where the light deficient environment 112 includesstructures, tissues, or other materials that emit a spectral response tocertain partitions of the electromagnetic spectrum, the pulsing schememay further include the emission of a hyperspectral partition ofelectromagnetic radiation for the purpose of eliciting the spectralresponse from the structures, tissues, or other materials present in thelight deficient environment 112. The spectral response includes theemission or reflection of certain wavelengths of electromagneticradiation. The spectral response can be sensed by the pixel array 122and result in a hyperspectral exposure frame. The hyperspectral exposureframe may be combined with multiple other exposure frames to form animage frame. The data in the hyperspectral exposure frame may beoverlaid on an RGB image frame that includes data from a red exposureframe, a green exposure frame, and a blue exposure frame.

In an embodiment, the pulsing scheme includes the emission of a lasermapping 110 pattern. The reflected electromagnetic radiation sensed bythe pixel array 122 following the emission of the laser mapping 110pattern results in a laser mapping exposure frame that includes thesensed laser mapping 111 data. The data in the laser mapping exposureframe may be provided to a corresponding system to identify, forexample, distances between tools present in the light deficientenvironment 112, a three-dimensional surface topology of a scene in thelight deficient environment 112, distances, dimensions, or positions ofstructures or objects within the scene, distances dimensions, orpositions of tools within the scene, and so forth. This data may beoverlaid on an RGB image frame or otherwise provided to a user of thesystem.

The emitter 102 may be a laser emitter that is capable of emittingpulsed red 104 light for generating sensed red 105 data for identifyingred 114 elements within the light deficient environment 112. The emitter102 is further capable of emitting pulsed green 106 light for generatingsensed green 107 data for identifying green 116 elements within thelight deficient environment. The emitter 102 is further capable ofemitting pulsed blue 108 light for generating sensed blue 109 data foridentifying blue 118 elements within the light deficient environment.The emitter 102 is further capable of emitting a laser mapping 110pulsing scheme for mapping the topology 120 of a scene within the lightdeficient environment 112. The emitter 102 is capable of emitting thepulsed red 104, pulsed green 106, pulsed blue 108, and pulsed lasermapping 110 pulsing schemes in any desired sequence.

The pixel array 122 senses reflected electromagnetic radiation. Each ofthe sensed red 105, the sensed green 107, the sensed blue 109, and thesensed laser mapping 111 data can be referred to as an “exposure frame.”Each exposure frame is assigned a specific color or wavelengthpartition, wherein the assignment is based on the timing of the pulsedcolor or wavelength partition from the emitter 102. The exposure framein combination with the assigned specific color or wavelength partitionmay be referred to as a dataset. Even though the pixels 122 are notcolor-dedicated, they can be assigned a color for any given datasetbased on a priori information about the emitter.

For example, during operation, after pulsed red 104 light is pulsed inthe light deficient environment 112, the pixel array 122 sensesreflected electromagnetic radiation. The reflected electromagneticradiation results in an exposure frame, and the exposure frame iscatalogued as sensed red 105 data because it corresponds in time withthe pulsed red 104 light. The exposure frame in combination with anindication that it corresponds in time with the pulsed red 104 light isthe “dataset.” This is repeated for each partition of electromagneticradiation emitted by the emitter 102. The data created by the pixelarray 122 includes the sensed red 105 exposure frame identifying red 114components in the light deficient environment and corresponding in timewith the pulsed red 104 light. The data further includes the sensedgreen 107 exposure frame identifying green 116 components in the lightdeficient environment and corresponding in time with the pulsed green106 light. The data further includes the sensed blue 109 exposure frameidentifying blue 118 components in the light deficient environment andcorresponding in time with the pulsed blue 108 light. The data furtherincludes the sensed laser mapping 111 exposure frame identifying thetopology 120 and corresponding in time with the laser mapping 110pulsing scheme.

In one embodiment, three datasets representing RED, GREEN and BLUEelectromagnetic pulses are combined to form a single image frame. Thus,the information in a red exposure frame, a green exposure frame, and ablue exposure frame are combined to form a single RGB image frame. Oneor more additional datasets representing other wavelength partitions maybe overlaid on the single RGB image frame. The one or more additionaldatasets may represent, for example, the laser mapping data,fluorescence imaging data, and/or hyperspectral imaging data.

It will be appreciated that the disclosure is not limited to anyparticular color combination or any particular electromagneticpartition, and that any color combination or any electromagneticpartition may be used in place of RED, GREEN and BLUE, such as Cyan,Magenta and Yellow; Ultraviolet; infrared; any combination of theforegoing, or any other color combination, including all visible andnon-visible wavelengths, without departing from the scope of thedisclosure. In the figure, the light deficient environment 112 to beimaged includes red 114, green 116, and blue 118 portions, and furtherincludes a topology 120 that can be sensed and mapped into athree-dimensional rendering. As illustrated in the figure, the reflectedlight from the electromagnetic pulses only contains the data for theportion of the object having the specific color that corresponds to thepulsed color partition. Those separate color (or color interval)datasets can then be used to reconstruct the image by combining thedatasets at 126. The information in each of the multiple exposure frames(i.e., the multiple datasets) may be combined by a controller 124, acontrol unit, a camera control unit, the image sensor, an image signalprocessing pipeline, or some other computing resource that isconfigurable to process the multiple exposure frames and combine thedatasets at 126. The datasets may be combined to generate the singleimage frame within the endoscope unit itself or offsite by some otherprocessing resource.

FIG. 2 is a system 200 for providing illumination to a light deficientenvironment, such as for endoscopic imaging. The system 200 may be usedin combination with any of the systems, methods, or devices disclosedherein. The system 200 includes an emitter 102, a controller 124, ajumper waveguide 206, a waveguide connector 208, a lumen waveguide 210,an endoscope 212, and an image sensor 214 with accompanying opticalcomponents (such as a lens). The emitter 102 (may be genericallyreferred to as a “light source”) generates light that travels throughthe jumper waveguide 206 and the lumen waveguide 210 to illuminate ascene at a distal end of the endoscope 212. The emitter 102 may be usedto emit any wavelength of electromagnetic energy including visiblewavelengths, infrared, ultraviolet, hyperspectral, fluorescenceexcitation, laser mapping pulsing schemes, or other wavelengths. Theendoscope 212 may be inserted into a patient's body for imaging, such asduring a procedure or examination. The electromagnetic radiation isoutput in a light cone 216 formation as illustrated by dashed lines. Ascene illuminated by the light may be captured using the image sensor214 and displayed for a doctor or some other medical personnel. Thecontroller 124 may provide control signals to the emitter 102 to controlwhen illumination is provided to a scene. In one embodiment, the emitter102 and controller 124 are located within a camera controller unit (CCU)or external console to which an endoscope is connected. If the imagesensor 214 includes a CMOS sensor, light may be periodically provided tothe scene in a series of illumination pulses between readout periods ofthe image sensor 214 during what is known as a blanking period. Thus,the light may be pulsed in a controlled manner to avoid overlapping intoreadout periods of the image pixels in a pixel array of the image sensor214.

In one embodiment, the lumen waveguide 210 includes one or more opticalfibers. The optical fibers may be made of a low-cost material, such asplastic to allow for disposal of the lumen waveguide 210 and/or otherportions of an endoscope. In one embodiment, the lumen waveguide 210 isa single glass fiber having a diameter of 500 microns. The jumperwaveguide 206 may be permanently attached to the emitter 102. Forexample, a jumper waveguide 206 may receive light from an emitter withinthe emitter 102 and provide that light to the lumen waveguide 210 at thelocation of the connector 208. In one embodiment, the jumper waveguide106 includes one or more glass fibers. The jumper waveguide may includeany other type of waveguide for guiding light to the lumen waveguide210. The connector 208 may selectively couple the jumper waveguide 206to the lumen waveguide 210 and allow light within the jumper waveguide206 to pass to the lumen waveguide 210. In one embodiment, the lumenwaveguide 210 is directly coupled to an emitter module without anyintervening jumper waveguide 206.

The image sensor 214 includes a pixel array. In an embodiment, the imagesensor 214 includes two or more pixel arrays for generating athree-dimensional image. The image sensor 214 may constitute two moreimage sensors that each have an independent pixel array and can operateindependent of one another. The pixel array of the image sensor 214includes active pixels and optical black (“OB”) or optically blindpixels. The active pixels may be clear “color agnostic” pixels that arecapable of sensing imaging data for any wavelength of electromagneticradiation. The optical black pixels are read during a blanking period ofthe pixel array when the pixel array is “reset” or calibrated. In anembodiment, light is pulsed during the blanking period of the pixelarray when the optical black pixels are being read. After the opticalblack pixels have been read, the active pixels are read during a readoutperiod of the pixel array. The active pixels may be charged by theelectromagnetic radiation that is pulsed during the blanking period suchthat the active pixels are ready to be read by the image sensor duringthe readout period of the pixel array.

FIG. 2A is a schematic diagram of complementary system hardware such asa special purpose or general-purpose computer. Implementations withinthe scope of the present disclosure may also include physical and othernon-transitory computer readable media for carrying or storing computerexecutable instructions and/or data structures. Such computer readablemedia can be any available media that can be accessed by a generalpurpose or special purpose computer system. Computer readable media thatstores computer executable instructions are computer storage media(devices). Computer readable media that carry computer executableinstructions are transmission media. Thus, by way of example, and notlimitation, implementations of the disclosure can comprise at least twodistinctly different kinds of computer readable media: computer storagemedia (devices) and transmission media.

Computer storage media (devices) includes RAM, ROM, EEPROM, CD-ROM,solid state drives (“SSDs”) (e.g., based on RAM), Flash memory,phase-change memory (“PCM”), other types of memory, other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium which can be used to store desired program code means inthe form of computer executable instructions or data structures andwhich can be accessed by a general purpose or special purpose computer.

A “network” is defined as one or more data links that enable thetransport of electronic data between computer systems and/or modulesand/or other electronic devices. In an implementation, a sensor andcamera controller may be networked to communicate with each other, andother components, connected over the network to which they areconnected. When information is transferred or provided over a network oranother communications connection (either hardwired, wireless, or acombination of hardwired or wireless) to a computer, the computerproperly views the connection as a transmission medium. Transmissionsmedia can include a network and/or data links, which can be used tocarry desired program code means in the form of computer executableinstructions or data structures and which can be accessed by a generalpurpose or special purpose computer. Combinations of the above shouldalso be included within the scope of computer readable media.

Further, upon reaching various computer system components, program codemeans in the form of computer executable instructions or data structuresthat can be transferred automatically from transmission media tocomputer storage media (devices) (or vice versa). For example, computerexecutable instructions or data structures received over a network ordata link can be buffered in RAM within a network interface module(e.g., a “NIC”), and then eventually transferred to computer system RAMand/or to less volatile computer storage media (devices) at a computersystem. RAM can also include solid state drives (SSDs or PCIx based realtime memory tiered storage, such as FusionIO). Thus, it should beunderstood that computer storage media (devices) can be included incomputer system components that also (or even primarily) utilizetransmission media.

Computer executable instructions comprise, for example, instructions anddata which, when executed by one or more processors, cause ageneral-purpose computer, special purpose computer, or special purposeprocessing device to perform a certain function or group of functions.The computer executable instructions may be, for example, binaries,intermediate format instructions such as assembly language, or evensource code. Although the subject matter has been described in languagespecific to structural features and/or methodological acts, it is to beunderstood that the subject matter defined in the appended claims is notnecessarily limited to the described features or acts described above.Rather, the described features and acts are disclosed as example formsof implementing the claims.

Those skilled in the art will appreciate that the disclosure may bepracticed in network computing environments with many types of computersystem configurations, including, personal computers, desktop computers,laptop computers, message processors, controllers, camera controllers,hand-held devices, hand pieces, multi-processor systems,microprocessor-based or programmable consumer electronics, network PCs,minicomputers, mainframe computers, mobile telephones, PDAs, tablets,pagers, routers, switches, various storage devices, and the like. Itshould be noted that any of the above-mentioned computing devices may beprovided by or located within a brick and mortar location. Thedisclosure may also be practiced in distributed system environmentswhere local and remote computer systems, which are linked (either byhardwired data links, wireless data links, or by a combination ofhardwired and wireless data links) through a network, both performtasks. In a distributed system environment, program modules may belocated in both local and remote memory storage devices.

Further, where appropriate, functions described herein can be performedin one or more of: hardware, software, firmware, digital components, oranalog components. For example, one or more application specificintegrated circuits (ASICs) or field programmable gate arrays (FPGAs)can be programmed to carry out one or more of the systems and proceduresdescribed herein. Certain terms are used throughout the followingdescription and Claims to refer to particular system components. As oneskilled in the art will appreciate, components may be referred to bydifferent names. This document does not intend to distinguish betweencomponents that differ in name, but not function.

FIG. 2A is a block diagram illustrating an example computing device 250.Computing device 250 may be used to perform various procedures, such asthose discussed herein. Computing device 250 can function as a server, aclient, or any other computing entity. Computing device 250 can performvarious monitoring functions as discussed herein, and can execute one ormore application programs, such as the application programs describedherein. Computing device 250 can be any of a wide variety of computingdevices, such as a desktop computer, a notebook computer, a servercomputer, a handheld computer, camera controller, tablet computer andthe like.

Computing device 250 includes one or more processor(s) 252, one or morememory device(s) 254, one or more interface(s) 256, one or more massstorage device(s) 258, one or more Input/Output (I/O) device(s) 260, anda display device 280 all of which are coupled to a bus 262. Processor(s)252 include one or more processors or controllers that executeinstructions stored in memory device(s) 254 and/or mass storagedevice(s) 258. Processor(s) 252 may also include various types ofcomputer readable media, such as cache memory.

Memory device(s) 254 include various computer readable media, such asvolatile memory (e.g., random access memory (RAM) 264) and/ornonvolatile memory (e.g., read-only memory (ROM) 266). Memory device(s)254 may also include rewritable ROM, such as Flash memory.

Mass storage device(s) 258 include various computer readable media, suchas magnetic tapes, magnetic disks, optical disks, solid-state memory(e.g., Flash memory), and so forth. As shown in FIG. 2, a particularmass storage device is a hard disk drive 274. Various drives may also beincluded in mass storage device(s) 258 to enable reading from and/orwriting to the various computer readable media. Mass storage device(s)258 include removable media 276 and/or non-removable media.

I/O device(s) 260 include various devices that allow data and/or otherinformation to be input to or retrieved from computing device 250.Example I/O device(s) 260 include digital imaging devices,electromagnetic sensors and emitters, cursor control devices, keyboards,keypads, microphones, monitors or other display devices, speakers,printers, network interface cards, modems, lenses, CCDs or other imagecapture devices, and the like.

Display device 280 includes any type of device capable of displayinginformation to one or more users of computing device 250. Examples ofdisplay device 280 include a monitor, display terminal, video projectiondevice, and the like.

Interface(s) 256 include various interfaces that allow computing device250 to interact with other systems, devices, or computing environments.Example interface(s) 256 may include any number of different networkinterfaces 270, such as interfaces to local area networks (LANs), widearea networks (WANs), wireless networks, and the Internet. Otherinterface(s) include user interface 268 and peripheral device interface272. The interface(s) 256 may also include one or more user interfaceelements 268. The interface(s) 256 may also include one or moreperipheral interfaces such as interfaces for printers, pointing devices(mice, track pad, etc.), keyboards, and the like.

Bus 262 allows processor(s) 252, memory device(s) 254, interface(s) 256,mass storage device(s) 258, and I/O device(s) 260 to communicate withone another, as well as other devices or components coupled to bus 262.Bus 262 represents one or more of several types of bus structures, suchas a system bus, PCI bus, IEEE 1394 bus, USB bus, and so forth.

For purposes of illustration, programs and other executable programcomponents are shown herein as discrete blocks, although it isunderstood that such programs and components may reside at various timesin different storage components of computing device 250 and are executedby processor(s) 252. Alternatively, the systems and procedures describedherein can be implemented in hardware, or a combination of hardware,software, and/or firmware. For example, one or more application specificintegrated circuits (ASICs) or field programmable gate arrays (FPGAs)can be programmed to carry out one or more of the systems and proceduresdescribed herein.

FIG. 3A illustrates the operational cycles of a sensor used in rollingreadout mode or during the sensor readout 300. The frame readout maystart at and may be represented by vertical line 310. The read-outperiod is represented by the diagonal or slanted line 302. The activepixels of the pixel array of the image sensor may be read out on a rowby row basis, the top of the downwards slanted edge being the sensor toprow 312 and the bottom of the downwards slanted edge being the sensorbottom row 314. The time between the last row readout and the nextreadout cycle may be called the blanking period 316. It should be notedthat some of the sensor pixel rows might be covered with a light shield(e.g., a metal coating or any other substantially black layer of anothermaterial type). These covered pixel rows may be referred to as opticalblack rows 318 and 320. Optical black rows 318 and 320 may be used asinput for correction algorithms. As shown in FIG. 3A, these opticalblack rows 318 and 320 may be located on the top of the pixel array orat the bottom of the pixel array or at the top and the bottom of thepixel array.

FIG. 3B illustrates a process of controlling the amount ofelectromagnetic radiation, e.g., light, that is exposed to a pixel,thereby integrated or accumulated by the pixel. It will be appreciatedthat photons are elementary particles of electromagnetic radiation.Photons are integrated, absorbed, or accumulated by each pixel andconverted into an electrical charge or current. An electronic shutter orrolling shutter (shown by dashed line 322) may be used to start theintegration time by resetting the pixel. The light will then integrateuntil the next readout phase. The position of the electronic shutter 322can be moved between two readout cycles 302 to control the pixelsaturation for a given amount of light. It should be noted that thistechnique allows for a constant integration time between two differentlines but introduces a delay when moving from top to bottom rows.

FIG. 3C illustrates the case where the electronic shutter 322 has beenremoved. In this configuration, the integration of the incoming lightmay start during readout 302 and may end at the next readout cycle 302,which also defines the start of the next integration.

FIG. 3D shows a configuration without an electronic shutter 322, butwith a controlled and pulsed light 330 during the blanking period 316.This ensures that all rows see the same light issued from the same lightpulse 330. In other words, each row will start its integration in a darkenvironment, which may be at the optical black back row 320 of read outframe (m) for a maximum light pulse width, and will then receive a lightstrobe and will end its integration in a dark environment, which may beat the optical black front row 318 of the next succeeding read out frame(m+1) for a maximum light pulse width. In the FIG. 3D example, the imagegenerated from the light pulse will be solely available during frame(m+1) readout without any interference with frames (m) and (m+2). Itshould be noted that the condition to have a light pulse to be read outonly in one frame and not interfere with neighboring frames is to havethe given light pulse firing during the blanking period 316. Because theoptical black rows 318, 320 are insensitive to light, the optical blackback rows 320 time of frame (m) and the optical black front rows 318time of frame (m+1) can be added to the blanking period 316 to determinethe maximum range of the firing time of the light pulse 330.

As illustrated in the FIG. 3A, a sensor may be cycled many times toreceive data for each pulsed color or wavelength (e.g., Red, Green,Blue, or other wavelength on the electromagnetic spectrum). Each cyclemay be timed. In an embodiment, the cycles may be timed to operatewithin an interval of 16.67 ms. In another embodiment, the cycles may betimed to operate within an interval of 8.3 ms. It will be appreciatedthat other timing intervals are contemplated by the disclosure and areintended to fall within the scope of this disclosure.

FIG. 4A graphically illustrates the operation of an embodiment of anelectromagnetic emitter. An emitter may be timed to correspond with thecycles of a sensor, such that electromagnetic radiation is emittedwithin the sensor operation cycle and/or during a portion of the sensoroperation cycle. FIG. 4A illustrates Pulse 1 at 402, Pulse 2 at 404, andPulse 3 at 406. In an embodiment, the emitter may pulse during thereadout period 302 of the sensor operation cycle. In an embodiment, theemitter may pulse during the blanking portion 316 of the sensoroperation cycle. In an embodiment, the emitter may pulse for a durationthat is during portions of two or more sensor operational cycles. In anembodiment, the emitter may begin a pulse during the blanking portion316, or during the optical black portion 320 of the readout period 302,and end the pulse during the readout period 302, or during the opticalblack portion 318 of the readout period 302 of the next succeedingcycle. It will be understood that any combination of the above isintended to fall within the scope of this disclosure as long as thepulse of the emitter and the cycle of the sensor correspond.

FIG. 4B graphically represents varying the duration and magnitude of theemitted electromagnetic pulse (e.g., Pulse 1 at 412, Pulse 2 at 414, andPulse 3 at 416) to control exposure. An emitter having a fixed outputmagnitude may be pulsed during any of the cycles noted above in relationto FIGS. 3D and 4A for an interval to provide the needed electromagneticenergy to the pixel array. An emitter having a fixed output magnitudemay be pulsed at a longer interval of time, thereby providing moreelectromagnetic energy to the pixels or the emitter may be pulsed at ashorter interval of time, thereby providing less electromagnetic energy.Whether a longer or shorter interval time is needed depends upon theoperational conditions.

In contrast to adjusting the interval of time the emitter pulses a fixedoutput magnitude, the magnitude of the emission itself may be increasedto provide more electromagnetic energy to the pixels. Similarly,decreasing the magnitude of the pulse provides less electromagneticenergy to the pixels. It should be noted that an embodiment of thesystem may have the ability to adjust both magnitude and durationconcurrently, if desired. Additionally, the sensor may be adjusted toincrease its sensitivity and duration as desired for optimal imagequality. FIG. 4B illustrates varying the magnitude and duration of thepulses. In the illustration, Pulse 1 at 412 has a higher magnitude orintensity than either Pulse 2 at 414 or Pulse 3 at 416. Additionally,Pulse 1 at 412 has a shorter duration than Pulse 2 at 414 or Pulse 3 at416, such that the electromagnetic energy provided by the pulse isillustrated by the area under the pulse shown in the illustration. Inthe illustration, Pulse 2 at 414 has a relatively low magnitude orintensity and a longer duration when compared to either Pulse 1 at 412or Pulse 3 at 416. Finally, in the illustration, Pulse 3 at 416 has anintermediate magnitude or intensity and duration, when compared to Pulse1 at 412 and Pulse 2 at 414.

FIG. 5 is a graphical representation of an embodiment of the disclosurecombining the operational cycles, the electromagnetic emitter, and theemitted electromagnetic pulses of FIGS. 3A-3D and 4A to demonstrate theimaging system during operation in accordance with the principles andteachings of the disclosure. As can be seen in the figure, theelectromagnetic emitter pulses the emissions primarily during theblanking period 316 of the image sensor such that the pixels will becharged and ready to read during the readout period 302 of the imagesensor cycle. The dashed lines in FIG. 5 represent the pulses ofelectromagnetic radiation (from FIG. 4A). The pulses of electromagneticradiation are primarily emitted during the blanking period 316 of theimage sensor but may overlap with the readout period 302 of the imagesensor.

An exposure frame includes the data read by the pixel array of the imagesensor during a readout period 302. The exposure frame may be combinedwith an indication of what type of pulse was emitted by the emitterprior to the readout period 302. The combination of the exposure frameand the indication of the pulse type may be referred to as a dataset.Multiple exposure frames may be combined to generate a black-and-whiteor RGB color image. Additionally, hyperspectral, fluorescence, and/orlaser mapping imaging data may be overlaid on a black-and-white or RGBimage.

In an embodiment, an exposure frame is the data sensed by the pixelarray during the readout period 302 that occurs subsequent to a blankingperiod 316. The emission of electromagnetic radiation is emitted duringthe blanking period 316. In an embodiment, a portion of the emission ofelectromagnetic radiation overlaps the readout period 316. The blankingperiod 316 occurs when optical black pixels of the pixel array are beingread and the readout period 302 occurs when active pixels of the pixelarray are being read. The blanking period 316 may overlap the readoutperiod 302.

FIGS. 6A and 6B illustrate processes for recording an image frame.Multiple image frames may be strung together to generate a video stream.A single image frame may include data from multiple exposure frames,wherein an exposure frame is the data sensed by a pixel array subsequentto an emission of electromagnetic radiation. FIG. 6A illustrates atraditional process that is typically implemented with a color imagesensor having a color filter array (CFA) for filtering out certainwavelengths of light per pixel. FIG. 6B is a process that is disclosedherein and can be implemented with a monochromatic “color agnostic”image sensor that is receptive to all wavelengths of electromagneticradiation.

The process illustrated in FIG. 6A occurs from time t(0) to time t(1).The process begins with a white light emission 602 and sensing whitelight 604. The image is processed and displayed at 606 based on thesensing at 604.

The process illustrated in FIG. 6B occurs from time t(0) to time t(1).The process begins with an emission of green light 612 and sensingreflected electromagnetic radiation 614 subsequent to the emission ofgreen light 612. The process continues with an emission of red light 616and sensing reflected electromagnetic radiation 618 subsequent to theemission of red light 616. The process continues with an emission ofblue light 620 and sensing reflected electromagnetic radiation 622subsequent to the emission of blue light 620. The process continues withone or more emissions of a laser mapping 624 pulsing scheme and sensingreflected electromagnetic energy 626 subsequent to each of the one ormore emissions of the laser mapping 624 pulsing scheme. The image isprocessed and displayed at 628 based on each of the sensed reflectedelectromagnetic energy instances 614, 618, 622, and 626.

The process illustrated in FIG. 6B provides a higher resolution imageand provides a means for generating an RGB image that further includeslaser mapping data. When partitioned spectrums of light are used, (as inFIG. 6B) a sensor can be made sensitive to all wavelengths ofelectromagnetic energy. In the process illustrated in FIG. 6B, themonochromatic pixel array is instructed that it is sensingelectromagnetic energy from a predetermined partition of the fullspectrum of electromagnetic energy in each cycle. Therefore, to form animage the sensor need only be cycled with a plurality of differingpartitions from within the full spectrum of light. The final image isassembled based on the multiple cycles. Because the image from eachcolor partition frame cycle has a higher resolution (compared with a CFApixel array), the resultant image created when the partitioned lightframes are combined also has a higher resolution. In other words,because each and every pixel within the array (instead of, at most,every second pixel in a sensor with a CFA) is sensing the magnitudes ofenergy for a given pulse and a given scene, just fractions of timeapart, a higher resolution image is created for each scene.

As can be seen graphically in the embodiments illustrated in FIGS. 6Aand 6B between times t(0) and t(1), the sensor for the partitionedspectrum system in FIG. 6B has cycled at least four times for every oneof the full spectrum system in FIG. 6A. In an embodiment, a displaydevice (LCD panel) operates at 50-60 frames per second. In such anembodiment, the partitioned light system in FIG. 6B may operate at200-240 frames per second to maintain the continuity and smoothness ofthe displayed video. In other embodiments, there may be differentcapture and display frame rates. Furthermore, the average capture ratecould be any multiple of the display rate.

In an embodiment, it may be desired that not all partitions berepresented equally within the system frame rate. In other words, notall light sources have to be pulsed with the same regularity so as toemphasize and de-emphasize aspects of the recorded scene as desired bythe users. It should also be understood that non-visible and visiblepartitions of the electromagnetic spectrum may be pulsed together withina system with their respective data value being stitched into the videooutput as desired for display to a user.

An embodiment may comprise a pulse cycle pattern as follows:

i. Green pulse;

ii. Red pulse;

iii. Blue pulse;

iv. Green pulse;

v. Red pulse;

vi. Blue pulse;

vii. Laser mapping pulse;

viii. (Repeat)

An embodiment may comprise a pulse cycle pattern as follows:

i. Luminance pulse;

ii. Red chrominance pulse;

iii. Luminance pulse;

iv. Blue chrominance pulse;

v. Laser mapping pulse;

vi. (Repeat)

An embodiment may comprise a pulse cycle pattern as follows:

i. Luminance pulse;

ii. Red chrominance pulse;

iii. Luminance pulse;

iv. Blue chrominance pulse;

v. Luminance pulse;

vi. Red chrominance pulse;

vii. Luminance pulse;

viii. Blue chrominance pulse;

ix. Laser mapping pulse;

x. (Repeat)

As can be seen in the example, a laser mapping partition may be pulsedat a rate differing from the rates of the other partition pulses. Thismay be done to emphasize a certain aspect of the scene, with the lasermapping data simply being overlaid with the other data in the videooutput to make the desired emphasis. It should be noted that theaddition of a laser mapping partition on top of the RED, GREEN, and BLUEpartitions does not necessarily require the serialized system to operateat four times the rate of a full spectrum non-serial system becauseevery partition does not have to be represented equally in the pulsepattern. As seen in the embodiment, the addition of a partition pulsethat is represented less in a pulse pattern (laser mapping in the aboveexample), would result in an increase of less than 20% of the cyclingspeed of the sensor to accommodate the irregular partition sampling.

The partition cycles may be divided so as to accommodate or approximatevarious imaging and video standards. In an embodiment, the partitioncycles comprise pulses of electromagnetic energy in the Red, Green, andBlue spectrum as follows as illustrated best in FIGS. 7A-7D. The timingrelationship between the emission of pulses of electromagnetic radiationby the emitter, and the readout of the pixel array is furtherillustrated in FIGS. 7A-7D.

In an embodiment, the emitter emits one or more hyperspectral emissionsfor eliciting a spectral response. The hyperspectral emissions includeone or more of electromagnetic radiation having a wavelength from about513-545 nm, from about 565-585 nm, and/or from about 900-1000 nm. Insuch an embodiment, the coherent light source 802 includes at least onelaser emitter for the 513-545 nm partition, at least one laser emitterfor the 565-585 partition, and at least one laser emitter for the900-1000 nm partition. It should be appreciated that additionalhyperspectral emissions for eliciting a spectral response can be emittedwithout departing from the scope of the disclosure.

In an embodiment, the emitter emits one or more fluorescence excitationemissions for fluorescing a reagent. The fluorescence excitationemissions include one or more of electromagnetic radiation having awavelength from about 460-470 nm, 529-537 nm. 633-643 nm, 775-785 nm,800-810 nm, 970-980 nm, 575-579 nm, 519-527 nm, 770-790 nm, and/or795-815 nm. In such an embodiment, the coherent light source 802 mayinclude at least one laser emitter for each of the aforementionedpartitions of electromagnetic radiation. It should be appreciated thatadditional fluorescence excitation emissions for fluorescing a reagentcan be emitted without departing from the scope of the disclosure.

In FIG. 7A, the different light intensities have been achieved bymodulating the light pulse width or duration within the working rangeshown by the vertical grey dashed lines. FIG. 7A illustrates the generaltiming relationships within a four-frame cycle, between pulsed mixturesof three wavelengths and the readout cycle of the pixel array of theimage sensor. In an embodiment, there are three monochromatic pulsedlight sources under the control of the controller. Periodic sequences ofmonochromatic red, monochromatic green, and monochromatic blue exposureframes are captured, e.g. with an R-G-B-G pulsing pattern and assembledinto an sRGB image frame by the image signal processor chain.

In FIG. 7B, the different light intensities have been achieved bymodulating the light power or the power of the electromagnetic emitter,which may be a laser or LED emitter, but keeping the pulse width orduration constant.

FIG. 7C shows the case where both the light power and the light pulsewidth are being modulated, leading to greater flexibility. The partitioncycles may use Cyan Magenta Yellow (CMY), infrared, ultraviolet,hyperspectral, and fluorescence using a non-visible pulse source mixedwith visible pulse sources and any other color space required to producean image or approximate a desired video standard that is currently knownor yet to be developed. It should also be understood that a system maybe able to switch between the color spaces on the fly to provide thedesired image output quality.

In an embodiment using color spaces Green-Blue-Green-Red (as seen inFIG. 7D) it may be desirous to pulse the luminance components more oftenthan the chrominance components because users are generally moresensitive to light magnitude differences than to light colordifferences. This principle can be exploited using a monochromatic imagesensor as illustrated in FIG. 7D. In FIG. 7D, green, which contains themost luminance information, may be pulsed more often or with moreintensity in a (G-B-G-R-G-B-G-R . . . ) scheme to obtain the luminancedata. Such a configuration would create a video stream that hasperceptively more detail, without creating and transmittingunperceivable data.

In an embodiment, all three sources of light are pulsed in unison withlight energies that are modulated to provide pure luminance informationin the same exposure frame. The light energies may be modulatedaccording to color transformation coefficients that convert from RGBcolor space to YCbCr color space. It should be appreciated that thecolor transformation may be implemented according to any suitablestandard such as the ITU-R BT.709 HD standard, the ITU-R BT.601standard, the ITU-R BT.2020 standard, or any other suitable standard orformula. The conversion may be performed according to the ITU-R BT.709HD standard as follows:

$\begin{bmatrix}Y \\{Cb} \\{Cr}\end{bmatrix} = {\begin{bmatrix}R \\G \\B\end{bmatrix}\begin{bmatrix}0.183 & 0.614 & 0.062 \\{- 0.101} & {- 0.339} & 0.439 \\0.439 & {- 0.399} & {- 0.040}\end{bmatrix}}$

In addition to the modulation of luminance information, a full colorimage further requires the red chrominance and blue chrominancecomponents. However, the algorithm applied for the luminance componentcannot be directly applied for chrominance componence because thealgorithm is signed as reflected in the fact that some of the RGBcoefficients are negative. In an embodiment, a degree of luminance isadded so that all of the final pulse energies are a positive value. Aslong as the color fusion process in the image signal processor is awareof the composition of the chrominance exposure frames, they can bedecoded by subtracting the appropriate amount of luminance from aneighboring frame. The pulse energy proportions are given by:Y=0.183·R+0.614·G+0.062·BCb=λ·Y−0.101·R−0.339·G+0.439·BCr=δ·Y+0.439·R−0.399·G−0.040·B

where

$\quad{\quad{{\lambda \geq \frac{0.339}{0.614}} = {{{0.552\delta} \geq \frac{0.399}{0.614}} = 0.650}}}$

If the λ factor is equal to 0.552, the red and green components arecancelled. In the case, the blue chrominance information can be providedwith pure blue light. Similarly, if the δ factor is equal to 0.650, theblue and green components are cancelled, and the red chrominanceinformation can be provided with pure red light. This embodiment is aconvenient approximation for digital frame reconstruction.

In an embodiment where white balance is performed in the illuminationdomain, then the modulation is imposed in addition to the white balancemodulation.

In an embodiment, duplicating the pulse of a weaker partition may beused to produce an output that has been adjusted for the weaker pulse.For example, blue laser light is considered weak relative to thesensitivity of silicon-based pixels and is difficult to produce incomparison to the red or green light, and therefore may be pulsed moreoften during a frame cycle to compensate for the weakness of the light.These additional pulses may be done serially over time or by usingmultiple lasers that simultaneously pulse to produce the desiredcompensation effect. It should be noted that by pulsing during ablanking period (time during which the sensor is not reading out thepixel array), the sensor is insensitive to differences/mismatchesbetween lasers of the same kind and simply accumulates the light for thedesired output. In another embodiment, the maximum light pulse range maybe different from frame to frame. This is shown in FIG. 7E, where thelight pulses are different from frame to frame. The sensor may be builtto be able to program different blanking periods with a repeatingpattern of two or three or four or n frames.

In FIG. 7E, four different light pulses are illustrated, and Pulse 1 mayrepeat for example after Pulse 4 and may have a pattern of four frameswith different blanking periods. This technique can be used to place themost powerful partition on the smallest blanking period and thereforeallow the weakest partition to have wider pulse on one of the nextframes without the need of increasing the readout speed. Thereconstructed frame can still have a regular pattern from frame to frameas it is constituted of many pulsed frames.

FIG. 8 is a graphical display of the delay or jitter between a controlsignal 802 and an emission 804 of electromagnetic radiation. In anembodiment, the control signal 802 represents a signal provided to thedriver of an emitter. The driver is configured to cause an emitter 102to emit a pulse of electromagnetic radiation. In an embodiment, thedriver is a component of a controller 124 or may be independent of thecontroller 124 and in communication with the controller 124. In anembodiment, the driver is the controller 124. In an embodiment, thedriver is a component of the emitter 102 or is in communication with theemitter 102. As illustrated, there is a delay of duration t1 between thecontrol signal 802 reaching its peak (i.e. turning on) and the emission804 of electromagnetic radiation by an emitter 102. There is a delay ofduration t2 between the control signal 802 going low (i.e. turning off)and the end of the emission 804 of electromagnetic radiation.

The delays t1 and t2 may include some constant delay as well as somenon-constant variation resulting from jitter in the driver of theemitter. For example, there may be a constant delay from when thecontrol signal 802 is transmitted to the driver and when an emission 804of electromagnetic radiation is actually emitted by the emitter 102.This delay may be very short and may be based on the time required forelectrical communications to occur between the driver and the emitter.Non-constant variation in the delay may be a result of jitter in thedriver of the emitter, in the controller 124, and or in the emitteritself.

The jitter experienced by a system or a component of a system (such asthe driver of the emitter) may be described by a value referred to asthe jitter specification. The jitter specification is a numerical valuethat describes the amount of jitter, or a duration of jitter,experienced by a system. In the example illustrated in FIG. 8, the delayt1 has a shorter duration than the delay t2. In the example, the delayt1 may represent the constant delay experienced after the control signal802 is initiated and an emission 804 of electromagnetic radiation isemitted by the emitter. The difference between t2 and t1 may representthe jitter experienced by the system. This value may be referred to asthe jitter specification.

In an embodiment, the jitter specification is a numerical value thatrepresents the amount of variation in the constant or predictable delayfor initiating or discontinuing an emission of a pulse ofelectromagnetic radiation. In such an embodiment, the system experiencesa constant, predictable delay between a driver signaling to the emitterto emit a pulse of electromagnetic radiation and when the emitteractually initiates the pulse of electromagnetic radiation. Similarly,there may be a constant, predictable delay between when the emittershould discontinue the pulse of electromagnetic radiation and when theemitter actually discontinues the pulse of electromagnetic radiation.This constant, predictable delay does not represent the jitterspecification. Instead, the jitter specification is the variation inthis constant, predictable delay. In the example illustrated in FIG. 8,the difference between times t2 and t1 represents the variation in theconstant, predictable delay.

Jitter is not under control by a user of the system. The jitterspecification represents the amount of unpredictable and non-constanttime variation present in the system. If the jitter specification is toolarge with respect to a pulse of electromagnetic radiation, significantreductions in image quality or image brightness variations can occur inthe resulting exposure frames. For example, in a video endoscopic systemas discussed herein, a long jitter specification can cause differentlines of exposure frames within a video stream to have differentbrightness. This leads to flickering and overall reduced quality in thevideo stream. A long jitter specification may result in light beingemitted during a readout period 302 of the image sensor. Ifelectromagnetic radiation is pulsed during the readout period 302,significant variations between pixels and rows of pixels in the pixelreadout will occur and this will reduce image quality in the resultantvideo stream.

In an example implementation, the controller 124 has a jitterspecification of 10% of the duration of a pulse of electromagneticradiation. In the example, the pulse may vary from 90% of its desiredduration to 110% of its desired duration. This can lead to brightnessvariations between exposure frames or lines within an image frame of avideo of up to one-third.

In an embodiment, if the jitter specification has a duration longer thana threshold amount, then the pulses of electromagnetic radiation arelimited in duration to avoid overlapping into a readout period 302.Limits on the pulse duration may require a reduction in frame rate byincreasing the time between captured exposure frames and/or increasingthe duration of the blanking period 316. This may result in a reductionto image brightness, and this may further reduce the ability of theimage sensor to capture detailed images.

In an embodiment, if the jitter specification has a duration shorterthan a threshold amount, then the pulsing sequence of the emitter 102and the readout sequence 204 of the image sensor remain unchanged. In anembodiment, the threshold indicates that the jitter specification mustbe 1 microsecond or less. In an embodiment, the threshold indicates thatthe jitter specification must be 50 nanoseconds or less. In anembodiment, the threshold indicates that the jitter specification mustbe less than the time it takes for the image sensor to read out one lineof the pixel array. In an embodiment, the threshold indicates that thejitter specification must be less than the time it takes for the imagesensor to read out a single pixel of the pixel array. In an embodiment,the threshold indicates that the jitter specification may be less thanor equal to 10% to 25% of the readout period 302 of the image sensor, orthe time it takes the image sensor to read out all active pixels in thepixel array. For example, in such an embodiment, if the pixel arraycomprises 400 lines, then the jitter specification must be less than orequal to the time required to read out 40-100 lines of the 400 lines inthe pixel array. Thus, the amount of variation in the light captured bythe pixel array may be low enough to reduce image flicked and provide asmuch light as possible between readout periods 302.

In an embodiment, the jitter specification is reduced (shortened) byimplementing a higher clock rate or a more accurate clock in thecontroller 124 or the driver of the emitter 102. The reduced jitterspecification and tolerance of the driver of the emitter 102 may solvethe problem of non-tolerated driving causing artifacts in the resultantvideo stream.

In an embodiment, a camera control unit (CCU) provides signals to acontroller 124 or an emitter 102 to avoid overlapping a pulse ofelectromagnetic radiation with the readout period 302 of the imagesensor. The CCU may determine a timing for sending a signal to thecontroller 124 and/or the emitter 102 to avoid overlapping into thereadout of active (i.e., not optical black) pixels of the pixel array.The CCU may maximize the duration of time electromagnetic radiation isemitted by the emitter 102 without overlapping a readout period 302 ofthe image sensor.

FIG. 9 illustrates a cross section of an optical fiber bundle 900 forcarrying electromagnetic radiation from an emitter 102 to a lightdeficient environment for illuminating a scene. In the exampleembodiment illustrated in FIG. 9, the optical fiber bundle 900 includesseven fibers, but it should be appreciated that the number of fibers isillustrative only and any suitable number of fibers may be used withdeparting from the scope of the disclosure. The fiber bundle includes acenter fiber 902 and multiple surrounding fibers 904.

In an embodiment, the total number of fibers is limited to reduce thecross-sectional area of the optical fiber bundle 900. The optical fiberbundle 900 may include a suitable number of fibers for providingsufficient light dispersion while allowing for a small cross-sectionalarea. This may be desirable because the cross-sectional rea of the lumenof an endoscopic is of critical importance in some applications where asmall endoscope is necessary. In an embodiment, the optical fiber bundle900 includes from two to 150 fibers. A smaller number of fibers mayreduce expense and the cross-sectional area needed to carry the opticalfiber bundle 900. However, a greater number of fibers improvesredundancy. In an embodiment, the optical fiber bundle 900 includes5-100 fibers, or 5-50 fibers, or 7-15 fibers. In an embodiment, theoptical fiber bundle includes seven fibers as illustrated in FIG. 9.

When the optical fiber bundle 900 has a smaller number of fibers, it maybe desirable that each fiber receives the same amount of electromagneticradiation and the same amount of a specific wavelength ofelectromagnetic radiation. For example, if electromagnetic radiation isprimarily transmitted through the center fiber 902, then the centerfiber 902 will receive a majority of the electromagnetic radiation andthe scene will be unevenly illuminated by color or brightness.Additionally, if more light enters into one fiber than another, theoverall amount of electromagnetic radiation (power) that can be carriedin the optical fiber bundle 900 may be reduced. For example, a fiber mayhave a burnout limit that may result in the fiber melting or otherwisebecoming inoperative if electromagnetic radiation above a certain energylevel or intensity is provided to the fiber. Thus, if electromagneticradiation is more evenly distributed across the fibers, then an increasein power and illumination of the scene may be possible.

In an embodiment, an emitter 102 mixes two or more wavelengths ofelectromagnetic radiation before providing the electromagnetic radiationto the optical fiber bundle 900. This may be accomplished when theemitter 102 includes two or more independent emitters for emittingdifferent wavelengths of electromagnetic radiation. The emitter 102 mayinclude, for example, a first emitter for emitting a first wavelengthand a second emitter for emitting a second wavelength. The emitter 102may mix the electromagnetic radiation such that light from the firstemitter and the second emitter enter the jumper waveguide (or anotherwaveguide) at the same or substantially same angle. A same orsubstantially same angle may be achieved by positioning the emitters atthe same angle relative to one another. In an embodiment, a dichroicmirror allows for a same or substantially same angle by reflectingelectromagnetic radiation of one wavelength while being transparent toanother wavelength. In an embodiment, the emitter 102 includes adiffuser, mixing rod, lens, or other optical element to mix light beforeentry into the optical fiber bundle 900.

In an embodiment, the emitter 102 provides an evenly distributed lightintensity to a waveguide. The peak intensity of light within a regionwhere light is collected for the waveguide may be substantially the sameor close to the average intensity of light over the region. The lightprovided to a collection region may have a top hat profile such thateach fiber collects and/or receives the same or similar intensity oflight. The emitter 102 may provide or approximate a top hat profile byproviding laser light at an angle to a surface of a collection region.For example, the emitter 102 may include a Gaussian or othernon-constant intensity profile. By angling the emitters in relation tothe collection region, the Gaussian profile is flattened into a moreconstant or top hat profile. The top hat profile may be generated usinglenses, diffusers, mixing rods, and the like.

FIG. 10 graphically illustrates a top hat profile 1002 and a Gaussianprofile 1004. The horizontal axis represents horizontal distance and thevertical axis represents light intensity. The lines labeled with callout1006 represent the boundaries or width of a collection region 1006 ofthe optical fiber bundle 900. The line labeled with the callout 1008represents a burnout level 1008 for a fiber or other waveguide.

With the Gaussian profile 1004, a majority of the electromagneticradiation is sent to the center fiber 902. When the majority of theenergy is in the center fiber 902, the remaining surrounding fibers 904may be far below the burnout level 1008. For example, with the Gaussianprofile 1004, an increase in the total amount of energy could lead to acenter fiber 902 significantly exceeding the burnout level 1008 with themultiple surround fibers 904 far below the burnout level 1008.

With the top hat profile 1002, all fibers carry the same energy level.This energy level may be near the burnout level 1008 or below theburnout level 1008. For example, with the top hat profile 1002, thetotal energy carried by the optical fiber bundle 900 may besignificantly increased because the optical fiber bundle 900 maycollectively be pushed near the burnout level 1008 without riskingburnout of any individual fiber.

FIG. 10 illustrates that more energy can be provided before any of theindividual fibers reach the burnout level 1008 by implementing the tophat profile 1002. In some instances, in traditional systems, the outputlight cone is smaller than the field of view (FOV) of the image sensor.The area of the output light cone is typically limited by the numericalaperture of the optical fiber of the waveguide. In these traditionalsystems, the distribution of light intensity within the output lightcone has an approximately Gaussian profile 1004. When the light outputhas a Gaussian profile 1004, the center of the image sensor's field ofview will be too bright and the edges of the image sensor's field ofview will be too dark. Therefore, it is desirable to provide even lightdistribution such that the entire field of view of the image sensor isuniform or nearly uniform.

The Gaussian profile 1004 and the top hat profile 1002 may provide thesame amount of wattage to the optical fiber bundle 900, while the tophat profile 1002 can still be increased significantly before reachingthe burnout level 1008. Thus, a significant improvement in the totalamount of energy delivered using plastic fibers can be achieved. In somecases, a 50% or greater increase of wattage carried by an optical fiberbundle 900 may be achieved by implementing the top hat profile 1002. Inan embodiment, the plastic fibers may have a burnout energy level forlight/electromagnetic energy emitted by the one or more emitters abovewhich damage to the plastic fibers may occur, wherein the light energyis spread out across the plurality of plastic fibers to allow a greateramount of energy to be carried by the optical fiber bundle 900 includingthe plastic fibers without reaching the burnout level 1008 in any of thefibers.

In an embodiment, the top hat profile 1002 and the Gaussian profile 1004are combined by an emitter 102 for use with plastic optical fiberbundles 900. The emitter 102 and/or the jumper waveguide may not includeplastic waveguides. However, the emitter 102 may mix the top hat profile1002 with the Gaussian profile 1004 to allow for use with a plasticoptical fiber bundle 900 at the lumen waveguide. In an embodiment,mixing the top hat profile 1002 allows for greater power delivery inview of losses that may be incurred when moving the electromagneticradiation between different materials, e.g. from a diffuser to a glassfiber, to a plastic fiber, and/or back to a glass fiber or diffuser. Thegreater power delivery may offset losses in previous or subsequenttransitions so that sufficient light can still be delivered toilluminate a scene.

FIG. 11 is a side view illustrating output from a waveguide 1102 incomparison to a camera field of view. In an embodiment, a plastic fiberhas a numerical aperture of 0.63 with a field of view of 100 degrees asindicated by dashed line 1106. A glass fiber has a numerical aperture of0.87 with a field of view of 120 degrees as indicated by solid line1104. However, light emitted within the field of view has an approximateGaussian profile within a light cone that is less than the field ofview. For example, nearly all the light for a plastic fiber may bewithin a cone of 80 degrees as indicated by dotted line 1108. Thus, acenter region of an exposure frame may be too bright while the edges aretoo dark.

FIG. 12 is a side view illustrating output from a waveguide comprisingan optical fiber bundle 1202 having a more uniform distribution of lightrelative to the output illustrated in FIG. 11. In the embodimentillustrated in FIG. 12, a uniform distribution of light is achieved byaiming the ends of fibers where light exits the optical fiber bundle1202. Aiming the fibers away from center broadens the cone in a field ofview with no light loss at the output. The end of each fiber may be heldin a desired position to distribute light where the combination of lightcones from the fibers provides even illumination. The optical fiberbundle 1202 includes a plurality of fibers and lines 1204 that indicatethe orientation of cones output by the individual fibers. In anembodiment, a fixture such as a physical mold or a sheet with holesholds the ends of the fibers in the desired orientations. The fibers maybe oriented in an optimal orientation for even illumination of a scene.The tips of the fibers in the optical fiber bundle 1202 may be locatednear a distal tip of an endoscope and may be pointed to spread lightaround a region centered on the focal point or camera lens axis.

FIG. 13 is a side view illustrating output from a waveguide comprisingan optical fiber bundle 1302 that transitions from plastic fibers 1304to glass fibers 1306 at a connector 1308. In the embodiment, a lumenwaveguide includes plastic fibers 1304 and then transitions to glassfibers 1306 at or near an output. The glass fibers 1306 generally have ahigher numerical aperture and a wider field of view than the plasticfibers 1304. Thus, a wider and more even distribution of light energy isachieved as illustrated by the light cone 1316. The light travelingthrough the plastic fibers 1304 is guided to the glass fibers 1306 byway of the connector 1308. This coupling may occur within a handpieceunit of an endoscope or a lumen of the endoscope. The connector 1308 maybe positioned in the handpiece unit or in the lumen to limit the amountof glass fibers 1306 used. Moving from plastic fibers 1304 through ataper in the handpiece or the lumen to glass fibers 1306 may result inthe same field of view as a conventional endoscope. However, light lossmay be significant, such as about 25% compared to the aiming embodiment,which experiences no light loss at the output.

FIG. 14 is a side view illustrating light output from a waveguidecomprising an optical fiber bundle 1402 using a diffuser 1408. In theembodiment, a lumen waveguide includes plastic fibers 1404 and thentransitions to the diffuser 1408 at or near an output. The diffuser 1408may include any suitable optical diffuser such as a mixing rod or thelike. Example diffusers include holographic diffusers. The diffuser 1408at the output can produce a larger angle for the field of view whencompared against glass fibers. However, the diffuser 1408 is lessefficient, such as about 40-60% efficient versus the aiming embodimentillustrated in FIG. 12.

Plastic fibers are typically less expensive than glass fibers. Thereduced price can lead to significant savings in manufacturing theillumination system. Because glass fibers may only be used for a shortdistance near an output, or not at all, a significant cost savings isrealized.

In an embodiment, a single fiber replaces an optical fiber bundle as thewaveguide. The single fiber may be larger than typical fibers making upthe optical fiber bundle such that the single fiber is capable ofhandling a greater amount of power than a bundle of smaller fibers forthe same cross-sectional area. The single fiber may extend from aconsole and through a lumen to provide light to an interior of a body orother light deficient environment. The single fiber may operate as alumen waveguide that extends from the emitter 102 or jumper waveguideand through a lumen. Electromagnetic radiation may be provided by theemitter 102 directly to the single fiber with the top hat profile.

Because a plastic fiber may only have a numerical aperture of 0.63 or0.65, most of the electromagnetic radiation may only exit the fiber atan angle of 70 or 80 degrees. At an output of the single fiber, adiffuser may be positioned to spread output light and create a more evenillumination within a field of the view of the camera. In an embodiment,the type of diffuser or the presence of a diffuser may be based on thefield of view used by the camera. For example, laparoscopic proceduresmay allow for more narrow fields of view, such as 70 degrees, whilearthroscopic procedures may use broader fields of view, such as 110degrees. Thus, a diffuser may be used for arthroscopic examinationswhile a diffuser is absent for laparoscopic examinations.

It should be understood that embodiments for outputting electromagneticradiation (light) may include a combination of one or more of theembodiments illustrated in FIGS. 11-14. For example, plastic fibers maybe transitioned to glass fibers and the glass fibers may be aimed toprovide more uniform and improved illumination.

FIG. 15 is a schematic diagram illustrating an example embodiment of asystem 1500 for providing illumination to a light deficient environment,such as for endoscopic imaging. The system 1500 illustrates analternative embodiment of transmitting light from the emitter module1502 to the endoscope 212 compared with the embodiment illustrated inthe system 200 of FIG. 2. The system 1500 includes an emitter module1502, a controller 124, a waveguide 1518, an endoscope 212, and an imagesensor 214 with accompanying optical components. In one embodiment, theemitter module 1502 and/or the controller 124 may be located in aconsole or camera control unit to which the endoscope 212 may beattached. The waveguide 1518 communicates electromagnetic radiation fromthe emitter module 1502 to the emitter 212 and may further communicateelectromagnetic radiation to the distal end of the endoscope 212 wherethe image sensor 214 is located.

Emissions of electromagnetic radiation exit the emitter module 1502 andthese emissions are provided into the waveguide 1518. Theelectromagnetic radiation travels through the waveguide 1518 toilluminate a scene at a distal end of the endoscope 212. The endoscope212 may be inserted into a patient's body for imaging, such as during aprocedure or examination. The electromagnetic radiation is output in alight cone 1516 formation as illustrated by dashed lines. A sceneilluminated by the electromagnetic radiation may be captured using theimage sensor 214 and displayed for a doctor or some other medicalpersonnel.

The emitter module 1502 generates and pulses electromagnetic radiation.The emitter module 1502 may include one or more emitters. In anembodiment, the emitter module 1502 includes a plurality of emitterssuch that the plurality of emitters may collectively pulse a range ofwavelengths of electromagnetic radiation. In an embodiment, each emitterwithin the emitter module 1502 is capable of pulsing one partition ofthe electromagnetic radiation and the emitter module 1502 includes aplurality of emitters for pulsing a plurality of wavelengths ofelectromagnetic radiation. As discussed herein, the term “emitter” mayrefer to any of the independent emitters within the emitter module 1502or may collectively refer to the emitter module 1502 itself. Therefore,the term “emitter” as used herein may refer to one or more individuallaser emitter units, a collection of a plurality of laser emitter units,and an emitter module 1502.

One or more emitters within the emitter module 1502 pulseelectromagnetic radiation. The electromagnetic radiation exits theemitter module 1502 and is provided into the waveguide 1518. In anembodiment, an optical fiber is attached to each of the independentemitters within the emitter module 1502, and these optical fibers arefed into the waveguide 1518. The waveguide 1518 may include one or moreoptical fibers for carrying electromagnetic radiation from the emittermodule 1502. The waveguide 1518 may include one or more of theembodiments included herein, such as the embodiments illustrated inFIGS. 11-14. As discussed herein, the term “waveguide” may refercollectively to the jumper waveguide 206 and the lumen waveguide 210illustrated in FIG. 2. The term “waveguide” may refer to either of thejumper waveguide 206 or the lumen waveguide 210 illustrated in FIG. 2.The term “waveguide” as used herein describes a component for carryingor transmitting light from one point to another point. As discussed withrespect to FIG. 15, the waveguide 1518 transmits electromagneticradiation from the emitter module 1502 to the endoscope 212 and/or thelight deficient environment being illuminated by the distal end of theendoscope 212.

In an embodiment, the waveguide 1518 is a single optical fiber extendingfrom the emitter module 1502, to the endoscope 212, through a lumen ofthe endoscope 212, and to the light deficient environment that is beingcaptured by the image sensor 214. In such an embodiment of the waveguide1518, the waveguide 1518 may be a single optical fiber with nointerruptions extending from the emitter module 1502 to the distal endof the endoscope 212. In an embodiment where the waveguide 1518 is asingle optical fiber rather than an optical fiber bundle (for example,the optical fiber bundle 900 illustrated in FIG. 9), the waveguide 1518may have a diameter of about 500 microns. The waveguide 1518 may be asingle plastic or glass optical fiber having a diameter of from about400 microns to about 600 microns. The waveguide 1518 may be a singleplastic or glass optical fiber having a diameter from about 450 micronsto about 550 microns.

In an embodiment, the waveguide 1518 is a single optical fiber connectedto the emitter module 1502 and then transitions to an optical fiberbundle at some point between the emitter module 1502 and the distal endof the endoscope 212. For example, the waveguide 1518 may be a singleoptical fiber at the connection point to the emitter module 1502, andthen may transition to an optical fiber bundle at a waveguide connector(such as the waveguide connector 208 illustrated in FIG. 2), at aproximal end of the endoscope 212, at some point within the endoscope212, or at a distal end of the endoscope 212. For example, the waveguide1518 may transition from a single optical fiber to an optical fiberbundle at some point before the waveguide 1518 reaches the endoscope212. For example, the waveguide 1518 may transition from a singleoptical fiber to an optical fiber bundle at some point within theendoscope 212, for example within the lumen of the endoscope 212. In anembodiment, the lumen includes a hollow rod that is disposed within abody for imaging the body, and the waveguide 1518 is disposed within thelumen along with other electrical components for supporting, forexample, the image sensor 214 and other optical components of thesystem. For example, the waveguide 1518 may transition from a singleoptical fiber to an optical fiber bundle at a distal end of theendoscope 212 near the image sensor 214.

In an embodiment, the reverse of the preceding paragraph is true suchthat the waveguide 1518 is an optical fiber bundle connected to theemitter module 1502 and then transitions to a single optical fiber atsome point between the emitter module 1502 and the distal end of theendoscope 212. It should be appreciated that the optical fiber bundlemay transition to a single optical fiber at any suitable point betweenthe emitter module 1502 and the distal end of the endoscope 212.

In some implementations, it may be desirable for the waveguide 1518 toconsist of a single optical fiber rather than an optical fiber bundle.This may be the case where the emitter is pulsing high-energy pulses ofelectromagnetic radiation. A single optical fiber with a certaindiameter may withstand a greater degree of energy than an optical fiberbundle that collectively has the same certain diameter. This is becauseof the individual optical fibers within the optical fiber bundle willhave a smaller diameter and will therefore be more prone to failure whentransmitting high-energy pulses of electromagnetic radiation.Particularly when optical fibers are constructed of plastic, opticalfibers may be exceedingly fragile and may fail or melt when exposed tohigh degrees of energy.

In some implementations, it may be desirable for the waveguide 1518 toconsist of an optical fiber bundle rather than a single optical fiber.An optical fiber bundle may have more longevity than a single opticalfiber because the optical fiber bundle includes a plurality of backupoptical fibers that can transmit electromagnetic radiation if one ormore of the optical fibers fails or breaks. Optical fibers can beexceedingly fragile, and it can be beneficial to transmitelectromagnetic radiation with more that one optical fiber at a time.

In some implementations, it may be desirable for the waveguide 1518 toinclude plastic optical fibers. In some alternate implementations, itmay be desirable for the waveguide 1518 to include glass optical fibers.Glass optical fibers may emit electromagnetic radiation in a wider lightcone 1516, and this may be beneficial when illuminating a lightdeficient environment such as an interior cavity of a body. The diameterof the light cone 1516 will also determine the size of the visibleregion within the light deficient environment. However, glass opticalfibers are exceedingly fragile and are much more expensive than plasticoptical fibers. In an embodiment, the waveguide 1518 includes one ormore plastic optical fibers and a diffuser disposed at the end of thewaveguide 1518. The diffuser may serve to widen the light cone 1516 ofelectromagnetic radiation exiting the waveguide 1518. In an embodiment,a waveguide 1518 consisting of one or more plastic optical fibers, incombination with a diffuser, may result in a wider light cone 1516compared with glass optical fibers without a diffuser.

In one embodiment, the waveguide 1518 includes a single plastic opticalfiber of about 500 microns. The plastic fiber may be low cost, but thewidth may allow the optical fiber to carry a sufficient amount ofelectromagnetic radiation to a scene, with coupling, diffuser, or otherlosses. In an embodiment, the waveguide 1518 includes a plurality ofoptical fibers. The waveguide 1518 may receive light directly from aconnection to the emitter module 1502 or via a jumper waveguide (e.g.,see the jumper waveguide 206 of FIG. 2). A diffuser may be used tobroaden the light cone 1516 for a desired field of view of the imagesensor 214 or other optical components.

FIG. 16 illustrates a system 1600 for providing electromagneticradiation to a light deficient environment for endoscopic imaging. Thesystem 1600 includes a camera control unit 1622 connected to anendoscope 1612. The camera control unit 1622 includes a controller 124and an emitter module 1602. The emitter module 1602 includes one or moreemitters for pulsing emissions of electromagnetic radiation. Emissionsof electromagnetic radiation exit the emitter module 1602 and areprovided to a waveguide 1618. The waveguide 1618 carries the emissionsof electromagnetic radiation at least to the hand unit of the endoscope1612 and may further carry the emissions of electromagnetic radiation tothe distal end of the endoscope lumen 1620 for illuminating the lightdeficient environment 112.

The waveguide 1618 may consist of a continuous optical fiber or opticalfiber bundle. The waveguide 1618 may include two or more sections ofoptical fiber(s) coupled together. The waveguide 1618 may include any ofthe embodiments disclosed herein, including those embodimentsillustrated in FIGS. 11-14. In an embodiment, the waveguide 1618 is acontinuous single optical fiber extending from the emitter module 1602to the distal end of the endoscope lumen 1620. In an embodiment, thewaveguide 1618 includes two or more sections of optical fiber(s) thatare coupled together at some point between the emitter module 1602 andthe distal end of the endoscope lumen 1620. In an embodiment, thewaveguide 1618 includes a first portion extending from the emittermodule 1602 to the endoscope 1612 (for example, the handpiece portion ofthe endoscope 1612). The first portion of the waveguide 1618 may then becoupled to a second portion beginning at the endoscope 1612 andterminating at the distal end of the endoscope lumen 1620.

The endoscope lumen 1620 is a component of the endoscope 1612. Thedistal end of the endoscope lumen 1620 may be inserted into the lightdeficient environment 112 for illuminating a scene. In animplementation, the distal end of the endoscope lumen 1620 is insertedinto a body cavity by way of a small incision. In an embodiment, theimage sensor is disposed at the distal end of the endoscope lumen 1620.Additionally, one or more optical fibers may terminate at the distal endof the endoscope lumen 1620 for illuminating the light deficientenvironment 112. The emissions of electromagnetic radiation exiting theoptical fibers at the distal end of the endoscope lumen 1620 create alight cone 1616 of illumination for visualizing a scene within the lightdeficient environment 112.

In an embodiment, the waveguide 1618 constitutes a single optical fiberfor carrying emissions of electromagnetic radiation from the emittermodule 1602 to the distal end of the endoscope lumen 1620, which may bedisposed within the light deficient environment 112. In an alternativeembodiment, the waveguide 1618 includes an optical fiber bundle with aplurality of optical fibers. The waveguide 1618 may be protected by andinserted within a tube that extends from the exit point of the emittermodule 1602 to a handpiece portion or other component of the endoscope1612. The waveguide 1618 may be disposed within a flexible tubing, suchas one constructed of plastic, rubber, silicone, or some other suitablematerial. The waveguide 1618 may extend from the emitter module 1602 tothe distal end of the endoscope lumen 1620.

In an embodiment, the endoscope lumen 1620 includes a rigid tube with acavity therein. The cavity within the endoscope lumen 1620 may be sizedappropriately for housing electrical components for the image sensor,including components for communications between the image sensor and thecamera control unit 1622. The cavity within the endoscope lumen 1620 mayadditionally include sufficient space for housing the waveguide 1618. Inan embodiment, the waveguide 1618 is disposed within a peripheral cavitythat surrounds an inner cavity, and the electrical components for theimage sensor are disposed within the inner cavity, as illustrated inFIGS. 17A-17B.

FIGS. 17A and 17B illustrate an exemplary embodiment for disposingoptical components and a waveguide within the endoscope lumen 1720. Inan embodiment, the endoscope lumen 1720 is a rigid, flexible, orsemi-flexible tube that may be inserted into the light deficientenvironment 112. The endoscope lumen 1720 may include an inner cavity1702 wherein optical components may be located. The optical componentsmay include wiring and other electrical connections for communicationsbetween the image sensor and/or the pixel array of the image sensor, andthe controller 124 and/or camera control unit 1622. The endoscope lumen1720 may additionally include a peripheral cavity 1704 for receiving thewaveguide 1618. In an embodiment, the waveguide 1618 is a single opticalfiber that may be disposed within the peripheral cavity 1704 along thelength of the endoscope lumen 1720. In an embodiment, the waveguide 1618is an optical fiber bundle comprising a plurality of optical fibers, andeach of the plurality of optical fibers is disposed within theperipheral cavity 1704 along the length of the endoscope lumen 1720.

FIG. 17B illustrates a straight-on exploded view of the distal end ofthe endoscope lumen 1720 and the components disposed within or attachedto the endoscope lumen 1720. In an embodiment, the image sensor 1706 islocated at the distal end of the endoscope lumen 1720. The system mayfurther include a lens 1708 located in front of the image sensor 1706with respect to the scene being imaged by the image sensor 1706, suchthat the lens 1708 is the distal-most point of the endoscope lumen 1720.The waveguide 1718 may be disposed within the peripheral cavity 1704 andmay terminate at the distal end of the endoscope lumen 1720 toilluminate a scene with pulses of electromagnetic radiation. Thesupporting electrical components for the image sensor 1706 may be storedwithin the inner cavity 1702 of the endoscope lumen 1720. In anembodiment, the waveguide 1718 extends past the distal-most point of theendoscope lumen 1720 to ensure proper illumination of the scene.

FIG. 18 illustrates an embodiment of an endoscope lumen 1820 and thelight cone 1816 of electromagnetic radiation exiting the endoscope lumen1820. In an embodiment, the waveguide 1818 is an optical fiber bundlecomprising a plurality of optical fibers. In such an embodiment, theplurality of optical fibers of the waveguide 1818 may be disposed withinthe peripheral cavity 1704 of the endoscope lumen 1820. In the exampleillustrated in FIG. 18, there are a plurality of optical fibers disposedwithin the peripheral cavity 1704 of the endoscope lumen 1820 such thatoptical fibers on the near side of the figure are illustrated with solidlines and optical fibers on the far side of the figure are illustratedwith dotted lines. The solid lines extending from the endoscope lumen1820 illustrate the beams of electromagnetic radiation emanating fromthe plurality of optical fibers of the waveguide 1818. These beams ofelectromagnetic radiation form a light cone 1816 of illumination.

FIGS. 19A-19C each illustrate an emitter 102 having a plurality ofemitters. The plurality of emitters may alternatively be referred to as“laser bundles,” wherein each emitter/laser bundle can operateindependently of the others and/or pulse different partitions orwavelengths of the electromagnetic spectrum. The emitter module 1900 cancollectively be referred to as an “emitter” herein. Therefore, the term“emitter” as used herein and in the appended claims should not be seenas limiting, and may refer to one or more emitters or lasers for pulsingelectromagnetic radiation, may refer to the collection of emitterswithin the emitter module 1900, and may refer to the emitter module 1900itself.

The plurality of emitters within the emitter module 1900 include a firstemitter 1902, a second emitter 1904, and a third emitter 1906.Additional emitters may be included, as discussed further below. Theemitters 1902, 1904, and 1906 may include one or more laser emittersthat emit light having different wavelengths. In an embodiment, one ormore of the emitters 1902, 1904, 1906 includes a bundle of lasers forpulsing a partition of the electromagnetic spectrum. For example, thefirst emitter 1902 may emit a wavelength that is consistent with a bluelaser, the second emitter 1904 may emit a wavelength that is consistentwith a green laser, and the third emitter 1906 may emit a wavelengththat is consistent with a red laser. For example, the first emitter 1902may include one or more blue lasers, the second emitter 1904 may includeone or more green lasers, and the third emitter 1906 may include one ormore red lasers. The emitters 1902, 1904, 1906 emit laser beams toward acollection region 1908, which may be the location of a waveguide, lens,or other optical component for collecting and/or providing light to awaveguide, such as the jumper waveguide 206 or lumen waveguide 210 ofFIG. 2.

In an embodiment, the emitter module 1900 includes one or more emitters1902, 1904, 1906 for emitting hyperspectral wavelengths ofelectromagnetic radiation. Certain hyperspectral wavelengths may piercethrough tissue and enable a medical practitioner to “see through”tissues in the foreground to identify chemical processes, structures,compounds, biological processes, and so forth that are located behindthe tissues in the foreground. The hyperspectral wavelengths may bespecifically selected to identify a specific disease, tissue condition,biological process, chemical process, type of tissue, and so forth thatis known to have a certain spectral response.

In an embodiment, the emitter module 1900 includes one or more emitters1902, 1904, 1906 for emitting fluorescence excitation wavelengths ofelectromagnetic radiation. In some implementations, a fluorescentreagent or dye may be administered to a patient, and the knownfluorescence excitation wavelength for fluorescing the reagent ispulsed. The fluorescence relaxation wavelength of the reagent may besensed by the system to generate a fluorescence exposure frame. Suchwavelength(s) may be determined based on the reagents or dyesadministered to the patient. In such an embodiment, the emitters mayneed to be highly precise for emitting desired wavelength(s) tofluoresce or activate certain reagents or dyes.

In an implementation, the emitter module 1900 includes one or moreemitters 1902, 1904, and 1906 for emitting a laser mapping pattern formapping a topology of a scene and/or for calculating dimensions anddistances between objects in the scene. In an embodiment, the endoscopicimaging system is used in conjunction with multiple tools such asscalpels, retractors, forceps, and so forth. In such an embodiment, eachof the emitters 1902, 1904, and 1906 may emit a laser mapping patternsuch that a laser mapping pattern is projected on to each toolindividually. In such an embodiment, the laser mapping data for each ofthe tools can be analyzed to identify distances between the tools andother objects in the scene.

In the embodiment of FIG. 19B, the emitters 1902, 1904, 1906 eachdeliver laser light to the collection region 1908 at different angles.The variation in angle can lead to variations where electromagneticenergy is located in an output waveguide. For example, if the lightpasses immediately into a fiber bundle (glass or plastic) at thecollection region 1908, the varying angles may cause different amountsof light to enter different fibers. For example, the angle may result inintensity variations across the collection region 1908. Furthermore,light from the different emitters may not be homogenously mixed so somefibers may receive different amounts of light of different colors.Variation in the color or intensity of light in different fibers canlead to non-optimal illumination of a scene. For example, variations indelivered light or light intensities may result at the scene andcaptured images.

In one embodiment, an intervening optical element may be placed betweena fiber bundle and the emitters 1902, 1904, 1906 to mix the differentcolors (wavelengths) of light before entry into the fibers or otherwaveguide. Example intervening optical elements include a diffuser,mixing rod, one or more lenses, or other optical components that mix thelight so that a given fiber receive a same amount of each color(wavelength). For example, each fiber in the fiber bundle may have asame color. This mixing may lead to the same color in each fiber butmay, in some embodiments, still result in different total brightnessdelivered to different fibers. In one embodiment, the interveningoptical element may also spread out or even out the light over thecollection region so that each fiber carries the same total amount oflight (e.g., the light may be spread out in a top hat profile). Adiffuser or mixing rod may lead to loss of light.

Although the collection region 1908 is represented as a physicalcomponent in FIG. 19A, the collection region 1908 may simply be a regionwhere light from the emitters 1902, 1904, and 1906 is delivered. In somecases, the collection region 1908 may include an optical component suchas a diffuser, mixing rod, lens, or any other intervening opticalcomponent between the emitters 1902, 1904, 1906 and an output waveguide.

FIG. 19C illustrates an embodiment of an emitter module 1900 withemitters 1902, 1904, 1906 that provide light to the collection region1908 at the same or substantially same angle. The light is provided atan angle substantially perpendicular to the collection region 1908. Theemitter module 1900 includes a plurality of dichroic mirrors including afirst dichroic mirror 1910, a second dichroic mirror 1912, and a thirddichroic mirror 1914. The dichroic mirrors 1910, 1912, 1914 includemirrors that reflect a first wavelength of light but transmit (or aretransparent to) a second wavelength of light. For example, the thirddichroic mirror 1914 may reflect blue laser light provided by the thirdemitter, while being transparent to the red and green light provided bythe first emitter 1902 and the second emitter 1904, respectively. Thesecond dichroic mirror 1912 may be transparent to red light from thefirst emitter 1902, but reflective to green light from the secondemitter 1904. If other colors or wavelengths are included dichroicmirrors may be selected to reflect light corresponding to at least oneemitter and be transparent to other emitters. For example, the thirddichroic mirror 1914 reflect the light form the third emitter 1906 butis to emitters “behind” it, such as the first emitter 1902 and thesecond emitter 1904. In embodiments where tens or hundreds of emittersare present, each dichroic mirror may be reflective to a correspondingemitter and emitters in front of it while being transparent to emittersbehind it. This may allow for tens or hundreds of emitters to emitelectromagnetic energy to the collection region 1908 at a substantiallysame angle.

Because the dichroic mirrors allow other wavelengths to transmit or passthrough, each of the wavelengths may arrive at the collection region1908 from a same angle and/or with the same center or focal point.Providing light from the same angle and/or same focal/center point cansignificantly improve reception and color mixing at the collectionregion 1908. For example, a specific fiber may receive the differentcolors in the same proportions they were transmitted/reflected by theemitters 1902, 1904, 1906 and mirrors 1910, 1912, 1914. Light mixing maybe significantly improved at the collection region compared to theembodiment of FIG. 19B. In one embodiment, any optical componentsdiscussed herein may be used at the collection region 1908 to collectlight prior to providing it to a fiber or fiber bundle.

FIG. 19C illustrates an embodiment of an emitter module 1900 withemitters 1902, 1904, 1906 that also provide light to the collectionregion 1908 at the same or substantially same angle. However, the lightincident on the collection region 1908 is offset from beingperpendicular. Angle 1916 indicates the angle offset from perpendicular.In one embodiment, the laser emitters 1902, 1904, 1906 may have crosssectional intensity profiles that are Gaussian. As discussed previously,improved distribution of light energy between fibers may be accomplishedby creating a more flat or top hat shaped intensity profile. In oneembodiment, as the angle 1916 is increased, the intensity across thecollection region 1908 approaches a top hat profile. For example, a tophat profile may be approximated even with a non-flat output beam byincreasing the angle 1916 until the profile is sufficiently flat. Thetop hat profile may also be accomplished using one or more lenses,diffusers, mixing rods, or any other intervening optical componentbetween the emitters 1902, 1904, 1906 and an output waveguide, fiber, oroptical fiber bundle.

FIG. 20 is a schematic diagram illustrating a single optical fiber 2002outputting via a diffuser 2004 at an output. In one embodiment, theoptical fiber 2002 has a diameter of 500 microns, a numerical apertureof 0.65, and emits a light cone 2016 of about 70 or 80 degrees without adiffuser 2004. With the diffuser 2004, the light cone 2016 may have anangle of about 110 or 120 degrees. The light cone 2016 may be a majorityof where all light goes and is evenly distributed. The diffuser 2004 mayallow for more even distribution of electromagnetic energy of a sceneobserved by an image sensor.

In one embodiment, the lumen waveguide 210 includes a single plastic orglass optical fiber of about 500 microns. The plastic fiber may be lowcost, but the width may allow the fiber to carry a sufficient amount oflight to a scene, with coupling, diffusion, or other losses. Forexample, smaller fibers may not be able to carry as much light or poweras a larger fiber. The lumen waveguide 210 may include a single or aplurality of optical fibers. The lumen waveguide 210 may receive lightdirectly from the emitter module or via a jumper waveguide. A diffusermay be used to broaden the light output 206 for a desired field of viewof the image sensor 214 or other optical components.

Although three emitters are shown in FIGS. 19A-19C, emitters numberingfrom one into the hundreds or more may be used in some embodiments. Theemitters may have different wavelengths or spectrums of light that theyemit, and which may be used to contiguously cover a desired portion ofthe electromagnetic spectrum (e.g., the visible spectrum as well asinfrared and ultraviolet spectrums). The emitters may be configured toemit visible light such as red light, green light, and blue light, andmay further be configured to emit hyperspectral emissions ofelectromagnetic radiation, fluorescence excitation wavelengths forfluorescing a reagent, and/or laser mapping patterns for calculatingparameters and distances between objects in a scene.

FIG. 21 illustrates a portion of the electromagnetic spectrum 2100divided into twenty different sub-spectrums. The number of sub-spectrumsis illustrative only. In at least one embodiment, the spectrum 2100 maybe divided into hundreds of sub-spectrums, each with a small waveband.The spectrum may extend from the infrared spectrum 2102, through thevisible spectrum 2104, and into the ultraviolet spectrum 2106. Thesub-spectrums each have a waveband 2108 that covers a portion of thespectrum 2100. Each waveband may be defined by an upper wavelength and alower wavelength.

Hyperspectral imaging includes imaging information from across theelectromagnetic spectrum 2100. A hyperspectral pulse of electromagneticradiation may include a plurality of sub-pulses spanning one or moreportions of the electromagnetic spectrum 2100 or the entirety of theelectromagnetic spectrum 2100. A hyperspectral pulse of electromagneticradiation may include a single partition of wavelengths ofelectromagnetic radiation. A resulting hyperspectral exposure frameincludes information sensed by the pixel array subsequent to ahyperspectral pulse of electromagnetic radiation. Therefore, ahyperspectral exposure frame may include data for any suitable partitionof the electromagnetic spectrum 2100 and may include multiple exposureframes for multiple partitions of the electromagnetic spectrum 2100. Inan embodiment, a hyperspectral exposure frame includes multiplehyperspectral exposure frames such that the combined hyperspectralexposure frame comprises data for the entirety of the electromagneticspectrum 2100.

In one embodiment, at least one emitter (such as a laser emitter) isincluded in an emitter module (such as the emitter modules 212, 102) foreach sub-spectrum to provide complete and contiguous coverage of thewhole spectrum 2100. For example, an emitter module for providingcoverage of the illustrated sub-spectrums may include at least 21different emitters, at least one for each sub-spectrum. In oneembodiment, each emitter covers a spectrum covering 40 nanometers. Forexample, one emitter may emit light within a waveband from 500 nm to 540nm while another emitter may emit light within a waveband from 540 nm to580 nm. In another embodiment, emitters may cover other sizes ofwavebands, depending on the types of emitters available or the imagingneeds. For example, a plurality of emitters may include a first emitterthat covers a waveband from 500 to 540 nm, a second emitter that coversa waveband from 540 nm to 640 nm, and a third emitter that covers awaveband from 640 nm to 650 nm. Each emitter may cover a different sliceof the electromagnetic spectrum ranging from far infrared, mid infrared,near infrared, visible light, near ultraviolet and/or extremeultraviolet. In some cases, a plurality of emitters of the same type orwavelength may be included to provide sufficient output power forimaging. The number of emitters needed for a specific waveband maydepend on the sensitivity of a monochrome sensor to the waveband and/orthe power output capability of emitters in that waveband.

The waveband widths and coverage provided by the emitters may beselected to provide any desired combination of spectrums. For example,contiguous coverage of a spectrum using very small waveband widths(e.g., 10 nm or less) may allow for highly selective hyperspectraland/or fluorescence imaging. The waveband widths may allow forselectively emitting the excitation wavelength(s) for one or moreparticular fluorescent reagents. Additionally, the waveband widths mayallow for selectively emitting certain partitions of hyperspectralelectromagnetic radiation for identifying specific structures, chemicalprocesses, tissues, biological processes, and so forth. Because thewavelengths come from emitters which can be selectively activated,extreme flexibility for fluorescing one or more specific fluorescentreagents during an examination can be achieved. Additionally, extremeflexibility for identifying one or more objects or processes by way ofhyperspectral imaging can be achieved. Thus, much more fluorescenceand/or hyperspectral information may be achieved in less time and withina single examination which would have required multiple examinations,delays because of the administration of dyes or stains, or the like.

FIG. 22 is a schematic diagram illustrating a timing diagram 2200 foremission and readout for generating an image. The solid line representsreadout (peaks 2202) and blanking periods (valleys) for capturing aseries of exposure frames 2204-2214. The series of exposure frames2204-2214 may include a repeating series of exposure frames which may beused for generating laser mapping, hyperspectral, and/or fluorescencedata that may be overlaid on an RGB video stream. In an embodiment, asingle image frame comprises information from multiple exposure frames,wherein one exposure frame includes red image data, another exposureframe includes green image data, and another exposure frame includesblue image data. Additionally, the single image frame may include one ormore of hyperspectral image data, fluorescence image data, and lasermapping data. The multiple exposure frames are combined to produce thesingle image frame. The single image frame is an RGB image withhyperspectral imaging data. The series of exposure frames include afirst exposure frame 2204, a second exposure frame 2206, a thirdexposure frame 2208, a fourth exposure frame 2210, a fifth exposureframe 2212, and an Nth exposure frame 2226.

Additionally, the hyperspectral image data, the fluorescence image data,and the laser mapping data can be used in combination to identifycritical tissues or structures and further to measure the dimensions ofthose critical tissues or structures. For example, the hyperspectralimage data may be provided to a corresponding system to identify certaincritical structures in a body such as a nerve, ureter, blood vessel,cancerous tissue, and so forth. The location and identification of thecritical structures may be received from the corresponding system andmay further be used to generate topology of the critical structuresusing the laser mapping data. For example, a corresponding systemdetermines the location of a cancerous tumor based on hyperspectralimaging data. Because the location of the cancerous tumor is known basedon the hyperspectral imaging data, the topology and distances of thecancerous tumor may then be calculated based on laser mapping data. Thisexample may also apply when a cancerous tumor or other structure isidentified based on fluorescence imaging data.

In one embodiment, each exposure frame is generated based on at leastone pulse of electromagnetic energy. The pulse of electromagnetic energyis reflected and detected by an image sensor and then read out in asubsequent readout (2202). Thus, each blanking period and readoutresults in an exposure frame for a specific spectrum of electromagneticenergy. For example, the first exposure frame 2204 may be generatedbased on a spectrum of a first one or more pulses 2216, a secondexposure frame 2206 may be generated based on a spectrum of a second oneor more pulses 2218, a third exposure frame 2208 may be generated basedon a spectrum of a third one or more pulses 2220, a fourth exposureframe 2210 may be generated based on a spectrum of a fourth one or morepulses 2222, a fifth exposure frame 2212 may be generated based on aspectrum of a fifth one or more pulses, and an Nth exposure frame 2226may be generated based on a spectrum of an Nth one or more pulses 2226.

The pulses 2216-2226 may include energy from a single emitter or from acombination of two or more emitters. For example, the spectrum includedin a single readout period or within the plurality of exposure frames2204-2214 may be selected for a desired examination or detection of aspecific tissue or condition. According to one embodiment, one or morepulses may include visible spectrum light for generating an RGB or blackand white image while one or more additional pulses are emitted to sensea spectral response to a hyperspectral wavelength of electromagneticradiation. For example, pulse 2216 may include red light, pulse 2218 mayinclude blue light, and pulse 2220 may include green light while theremaining pulses 2222-2226 may include wavelengths and spectrums fordetecting a specific tissue type, fluorescing a reagent, and/or mappingthe topology of the scene. As a further example, pulses for a singlereadout period include a spectrum generated from multiple differentemitters (e.g., different slices of the electromagnetic spectrum) thatcan be used to detect a specific tissue type. For example, if thecombination of wavelengths results in a pixel having a value exceedingor falling below a threshold, that pixel may be classified ascorresponding to a specific type of tissue. Each frame may be used tofurther narrow the type of tissue that is present at that pixel (e.g.,and each pixel in the image) to provide a very specific classificationof the tissue and/or a state of the tissue (diseased/healthy) based on aspectral response of the tissue and/or whether a fluorescent reagent ispresent at the tissue.

The plurality of frames 2204-2214 is shown having varying lengths inreadout periods and pulses having different lengths or intensities. Theblanking period, pulse length or intensity, or the like may be selectedbased on the sensitivity of a monochromatic sensor to the specificwavelength, the power output capability of the emitter(s), and/or thecarrying capacity of the waveguide.

In one embodiment, dual image sensors may be used to obtainthree-dimensional images or video feeds. A three-dimensional examinationmay allow for improved understanding of a three-dimensional structure ofthe examined region as well as a mapping of the different tissue ormaterial types within the region.

In an example implementation, a fluorescent reagent is provided to apatient, and the fluorescent reagent is configured to adhere tocancerous cells. The fluorescent reagent is known to fluoresce whenradiated with a specific partition of electromagnetic radiation. Therelaxation wavelength of the fluorescent reagent is also known. In theexample implementation, the patient is imaged with an endoscopic imagingsystem as discussed herein. The endoscopic imaging system pulsespartitions of red, green, and blue wavelengths of light to generate anRGB video stream of the interior of the patient's body. Additionally,the endoscopic imaging system pulses the excitation wavelength ofelectromagnetic radiation for the fluorescent reagent that wasadministered to the patient. In the example, the patient has cancerouscells and the fluorescent reagent has adhered to the cancerous cells.When the endoscopic imaging system pulses the excitation wavelength forthe fluorescent reagent, the fluorescent reagent will fluoresce and emita relaxation wavelength. If the cancerous cells are present in the scenebeing imaged by the endoscopic imaging system, then the fluorescentreagent will also be present in the scene and will emit its relaxationwavelength after fluorescing due to the emission of the excitationwavelength. The endoscopic imaging system senses the relaxationwavelength of the fluorescent reagent and thereby senses the presence ofthe fluorescent reagent in the scene. Because the fluorescent reagent isknown to adhere to cancerous cells, the presence of the fluorescentreagent further indicates the presence of cancerous cells within thescene. The endoscopic imaging system thereby identifies the location ofcancerous cells within the scene. The endoscopic imaging system mayfurther emit a laser mapping pulsing scheme for generating a topology ofthe scene and calculating dimensions for objects within the scene. Thelocation of the cancerous cells (as identified by the fluorescenceimaging data) may be combined with the topology and dimensionsinformation calculated based on the laser mapping data. Therefore, theprecise location, size, dimensions, and topology of the cancerous cellsmay be identified. This information may be provided to a medicalpractitioner to aid in excising the cancerous cells. Additionally, thisinformation may be provided to a robotic surgical system to enable thesurgical system to excise the cancerous cells.

In a further example implementation, a patient is imaged with anendoscopic imaging system to identify quantitative diagnosticinformation about the patient's tissue pathology. In the example, thepatient is suspected or known to suffer from a disease that can betracked with hyperspectral imaging to observe the progression of thedisease in the patient's tissue. The endoscopic imaging system pulsespartitions of red, green, and blue wavelengths of light to generate anRGB video stream of the interior of the patient's body. Additionally,the endoscopic imaging system pulses one or more hyperspectralwavelengths of light that permit the system to “see through” sometissues and generate imaging of the tissue that is affected by thedisease. The endoscopic imaging system senses the reflectedhyperspectral electromagnetic radiation to generate hyperspectralimaging data of the diseased tissue, and thereby identifies the locationof the diseased tissue within the patient's body. The endoscopic imagingsystem may further emit a laser mapping pulsing scheme for generating atopology of the scene and calculating dimensions of objects within thescene. The location of the diseased tissue (as identified by thehyperspectral imaging data) may be combined with the topology anddimensions information that is calculated with the laser mapping data.Therefore, the precise location, size, dimensions, and topology of thediseased tissue can be identified. This information may be provided to amedical practitioner to aid in excising, imaging, or studying thediseased tissue. Additionally, this information may be provided to arobotic surgical system to enable the surgical system to excise thediseased tissue.

FIG. 23 is a schematic diagram of an imaging system 2300 having a singlecut filter. The system 2300 includes an endoscope 2306 or other suitableimaging device having a light source 2308 for use in a light deficientenvironment. The endoscope 2306 includes an image sensor 2304 and afilter 2302 for filtering out unwanted wavelengths of light or otherelectromagnetic radiation before reaching the image sensor 2304. Thelight source 2308 transmits light that may illuminate the surface 2312in a light deficient environment such as a body cavity. The light 2310is reflected off the surface 2312 and passes through the filter 2302before hitting the image sensor 2304.

The filter 2302 may be used in an implementation where a fluorescentreagent or dye has been administered. In such an embodiment, the lightsource 2308 emits the excitation wavelength for fluorescing thefluorescent reagent or dye. Commonly, the relaxation wavelength emittedby the fluorescent reagent or dye will be of a different wavelength thanthe excitation wavelength. The filter 2302 may be selected to filter outthe excitation wavelength and permit only the relaxation wavelength topass through the filter and be sensed by the image sensor 2304.

In one embodiment, the filter 2302 is configured to filter out anexcitation wavelength of electromagnetic radiation that causes a reagentor dye to fluoresce such that only the expected relaxation wavelength ofthe fluoresced reagent or dye is permitted to pass through the filter2302 and reach the image sensor 2304. In an embodiment, the filter 2302filters out at least a fluorescent reagent excitation wavelength between770 nm and 790 nm. In an embodiment, the filter 2302 filters out atleast a fluorescent reagent excitation wavelength between 795 nm and 815nm. In an embodiment, the filter 2302 filters out at least a fluorescentreagent excitation wavelength between 770 nm and 790 nm and between 795nm and 815 nm. In these embodiments, the filter 2302 filters out theexcitation wavelength of the reagent and permits only the relaxationwavelength of the fluoresced reagent to be read by the image sensor2304. The image sensor 2304 may be a wavelength-agnostic image sensorand the filter 2302 may be configured to permit the image sensor 2304 toonly receive the relaxation wavelength of the fluoresced reagent and notreceive the emitted excitation wavelength for the reagent. The datadetermined by the image sensor 2304 may then indicate a presence of acritical body structure, tissue, biological process, or chemical processas determined by a location of the reagent or dye.

The filter 2302 may further be used in an implementation where afluorescent reagent or dye has not been administered. The filter 2302may be selected to permit wavelengths corresponding to a desiredspectral response to pass through and be read by the image sensor 2304.The image sensor 2304 may be a monochromatic image sensor such thatpixels of the captured image that exceed a threshold or fall below athreshold may be characterized as corresponding to a certain spectralresponse or fluorescence emission. The spectral response or fluorescenceemission, as determined by the pixels captured by the image sensor 2304,may indicate the presence of a certain body tissue or structure, acertain condition, a certain chemical process, and so forth.

FIG. 24 is a schematic diagram of an imaging system 2400 having multiplecut filters. The system 2400 includes an endoscope 2406 or othersuitable imaging device having a light source 2408 for use in a lightdeficient environment. The endoscope 2406 includes an image sensor 2404and two filters 2402 a, 2402 b. It should be appreciated that inalternative embodiments, the system 2400 may include any number offilters, and the number of filters and the type of filters may beselected for a certain purpose e.g., for gathering imaging informationof a particular body tissue, body condition, chemical process, and soforth. The filters 2402 a, 2402 b are configured for preventing unwantedwavelengths of light or other electromagnetic radiation from beingsensed by the image sensor 2404. The filters 2402 a, 2402 b may beconfigured to filter out unwanted wavelengths from white light or otherelectromagnetic radiation that may be emitted by the light source 2408.

Further to the disclosure with respect to FIG. 23, the filters 2402 a,2402 b may be used in an implementation where a fluorescent reagent ordye has been administered. The filters 2402 a, 2402 b may be configuredfor blocking an emitted excitation wavelength for the reagent or dye andpermitting the image sensor 2404 to only read the relaxation wavelengthof the reagent or dye. Further, the filters 2402 a, 2402 b may be usedin an implementation where a fluorescent reagent or dye has not beenadministered. In such an implementation, the filters 2402 a, 2402 b maybe selected to permit wavelengths corresponding to a desired spectralresponse to pass through and be read by the image sensor 2404.

The multiple filters 2402 a, 2402 b may each be configured for filteringout a different range of wavelengths of the electromagnetic spectrum.For example, one filter may be configured for filtering out wavelengthslonger than a desired wavelength range and the additional filter may beconfigured for filtering out wavelengths shorter than the desiredwavelength range. The combination of the two or more filters may resultin only a certain wavelength or band of wavelengths being read by theimage sensor 2404.

In an embodiment, the filters 2402 a, 2402 b are customized such thatelectromagnetic radiation between 513 nm and 545 nm contacts the imagesensor 2404. In an embodiment, the filters 2402 a, 2402 b are customizedsuch that electromagnetic radiation between 565 nm and 585 nm contactsthe image sensor 2404. In an embodiment, the filters 2402 a, 2402 b arecustomized such that electromagnetic radiation between 900 nm and 1000nm contacts the image sensor 2404. In an embodiment, the filters 2402 a,2402 b are customized such that electromagnetic radiation between 423 nmand 475 nm contacts the image sensor 2404. In an embodiment, the filters2402 a, 2402 b are customized such that electromagnetic radiationbetween 520 nm and 545 nm contacts the image sensor 2404. In anembodiment, the filters 2402 a, 2402 b are customized such thatelectromagnetic radiation between 617 nm and 645 nm contacts the imagesensor 2404. In an embodiment, the filters 2402 a, 2402 b are customizedsuch that electromagnetic radiation between 760 nm and 795 nm contactsthe image sensor 2404. In an embodiment, the filters 2402 a, 2402 b arecustomized such that electromagnetic radiation between 795 nm and 815 nmcontacts the image sensor 2404. In an embodiment, the filters 2402 a,2402 b are customized such that electromagnetic radiation between 370 nmand 420 nm contacts the image sensor 2404. In an embodiment, the filters2402 a, 2402 b are customized such that electromagnetic radiationbetween 600 nm and 670 nm contacts the image sensor 2404. In anembodiment, the filters 2402 a, 2402 b are configured for permittingonly a certain fluorescence relaxation emission to pass through thefilters 2402 a, 2402 b and contact the image sensor 2404. In anembodiment, a first filter blocks electromagnetic radiation having awavelength from about 770 nm to about 790 nm, and a second filter blockselectromagnetic radiation having a wavelength from about 795 nm to about815 nm.

In an embodiment, the system 2400 includes multiple image sensors 2404and may particularly include two image sensors for use in generating athree-dimensional image. The image sensor(s) 2404 may becolor/wavelength agnostic and configured for reading any wavelength ofelectromagnetic radiation that is reflected off the surface 2412. In anembodiment, the image sensors 2404 are each color dependent orwavelength dependent and configured for reading electromagneticradiation of a particular wavelength that is reflected off the surface2412 and back to the image sensors 2404. Alternatively, the image sensor2404 may include a single image sensor with a plurality of differentpixel sensors configured for reading different wavelengths or colors oflight, such as a Bayer filter color filter array. Alternatively, theimage sensor 2404 may include one or more color agnostic image sensorsthat may be configured for reading different wavelengths ofelectromagnetic radiation according to a pulsing schedule such as thoseillustrated in FIGS. 5-7E, for example.

FIG. 25 is a schematic diagram illustrating a system 2500 for mapping asurface and/or tracking an object in a light deficient environmentthrough laser mapping imaging. In an embodiment, an endoscope 2506 in alight deficient environment pulses a grid array 2506 (may be referred toas a laser map pattern) on a surface 2504. The grid array 2506 includesvertical hashing 2508 and horizontal hashing 2510 in one embodiment asillustrated in FIG. 25. It should be appreciated the grid array 2506 mayinclude any suitable array for mapping a surface 2504, including, forexample, a raster grid of discrete points, an occupancy grid map, a dotarray, and so forth. Additionally, the endoscope 2506 may pulse multiplegrid arrays 2506 and may, for example, pulse one or more individual gridarrays on each of a plurality of objects or structures within the lightdeficient environment.

In an embodiment, the system 2500 pulses a grid array 2506 that may beused for mapping a three-dimensional topology of a surface and/ortracking a location of an object such as a tool or another device in alight deficient environment. In an embodiment, the system 2500 providesdata to a third-party system or computer algorithm for determiningsurface dimensions and configurations by way of light detection andranging (LIDAR) mapping. The system 2500 may pulse any suitablewavelength of light or electromagnetic radiation in the grid array 2506,including, for example, ultraviolet light, visible, light, and/orinfrared or near infrared light. The surface 2504 and/or objects withinthe environment may be mapped and tracked at very high resolution andwith very high accuracy and precision.

In an embodiment, the system 2500 includes an imaging device having atube, one or more image sensors, and a lens assembly having an opticalelement corresponding to the one or more image sensors. The system 2500may include a light engine having an emitter generating one or morepulses of electromagnetic radiation and a lumen transmitting the one ormore pulses of electromagnetic radiation to a distal tip of an endoscope within a light deficient environment such as a body cavity. In anembodiment, at least a portion of the one or more pulses ofelectromagnetic radiation includes a laser map pattern that is emittedonto a surface within the light deficient environment, such as a surfaceof body tissue and/or a surface of tools or other devices within thebody cavity. The endoscope 2506 may include a two-dimensional,three-dimensional, or n-dimensional camera for mapping and/or trackingthe surface, dimensions, and configurations within the light deficientenvironment.

In an embodiment, the system 2500 includes a processor for determining adistance of an endoscope or tool from an object such as the surface2504. The processor may further determine an angle between the endoscopeor tool and the object. The processor may further determine surface areainformation about the object, including for example, the size ofsurgical tools, the size of structures, the size of anatomicalstructures, location information, and other positional data and metrics.The system 2500 may include one or more image sensors that provide imagedata that is output to a control system for determining a distance of anendoscope or tool to an object such as the surface 2504. The imagesensors may output information to a control system for determining anangle between the endoscope or tool to the object. Additionally, theimage sensors may output information to a control system for determiningsurface area information about the object, the size of surgical tools,size of structures, size of anatomical structures, location information,and other positional data and metrics.

In an embodiment, the grid array 2506 is pulsed by an emitter of theendoscope 2506 at a sufficient speed such that the grid array 2506 isnot visible to a user. In various implementations, it may be distractingto a user to see the grid array 2506 during an endoscopic imagingprocedure and/or endoscopic surgical procedure. The grid array 2506 maybe pulsed for sufficiently brief periods such that the grid array 2506cannot be detected by a human eye. In an alternative embodiment, theendoscope 2506 pulses the grid array 2506 at a sufficient recurringfrequency such that the grid array 2506 may be viewed by a user. In suchan embodiment, the grid array 2506 may be overlaid on an image of thesurface 2504 on a display. The grid array 2506 may be overlaid on ablack-and-white or RGB image of the surface 2504 such that the gridarray 2506 may be visible by a user during use of the system 2500. Auser of the system 2500 may indicate whether the grid array 2506 shouldbe overlaid on an image of the surface 2504 and/or whether the gridarray 2506 should be visible to the user. The system 2500 may include adisplay that provides real-time measurements of a distance from theendoscope 2506 to the surface 2504 or another object within the lightdeficient environment. The display may further provide real-time surfacearea information about the surface 2504 and/or any objects, structures,or tools within the light deficient environment. The accuracy of themeasurements may be accurate to less than one millimeter.

In an embodiment, the system 2500 pulses a plurality of grid arrays2506. In an embodiment, each of the plurality of grid arrays 2506corresponds to a tool or other device present within the light deficientenvironment. The precise locations and parameters of each of the toolsand other devices may be tracked by pulsing and sensing the plurality ofgrid arrays 2506. The information generated by sensing the reflectedgrid arrays 2506 can be assessed to identify relative locations of thetools and other devices within the light deficient environment.

The endoscope 2506 may pulse electromagnetic radiation according to apulsing schedule such as those illustrated herein that may furtherinclude pulsing of the grid array 2506 along with pulsing Red, Green,and Blue light for generating an RGB image and further generating a gridarray 2506 that may be overlaid on the RGB image and/or used for mappingand tracking the surface 2504 and objects within the light deficientenvironment. The grid array 2506 may additionally be pulsed inconjunction with hyperspectral or fluorescent excitation wavelengths ofelectromagnetic radiation. The data from each of the RGB imaging, thelaser mapping imaging, the hyperspectral imaging, and the fluorescenceimaging may be combined to identify the locations, dimensions, andsurface topology of critical structures in a body.

In an embodiment, the endoscope 2506 includes one or more color agnosticimage sensors. In an embodiment, the endoscope 2506 includes two coloragnostic image sensors for generating a three-dimensional image or mapof the light deficient environment. The image sensors may generate anRGB image of the light deficient environment according to a pulsingschedule as disclosed herein. Additionally, the image sensors maydetermine data for mapping the light deficient environment and trackingone or more objects within the light deficient environment based on datadetermined when the grid array 2506 is pulsed. Additionally, the imagesensors may determine spectral or hyperspectral data along withfluorescence imaging data according to a pulsing schedule that may bemodified by a user to suit the particular needs of an imaging procedure.In an embodiment, a pulsing schedule includes Red, Green, and Bluepulses along with pulsing of a grid array 2506 and/or pulsing forgenerating hyperspectral image data and/or fluorescence image data. Invarious implementations, the pulsing schedule may include any suitablecombination of pulses of electromagnetic radiation according to theneeds of a user. The recurring frequency of the different wavelengths ofelectromagnetic radiation may be determined based on, for example, theenergy of a certain pulse, the needs of the user, whether certain data(for example, hyperspectral data and/or fluorescence imaging data) needsto be continuously updated or may be updated less frequently, and soforth.

The pulsing schedule may be modified in any suitable manner, and certainpulses of electromagnetic radiation may be repeated at any suitablefrequency, according to the needs of a user or computer-implementedprogram for a certain imaging procedure. For example, in an embodimentwhere surface tracking data generated based on the grid array 2506 isprovided to a computer-implemented program for use in, for example, arobotic surgical procedure, the grid array 2506 may be pulsed morefrequently than if the surface tracking data is provided to a user whois visualizing the scene during the imaging procedure. In such anembodiment where the surface tracking data is used for a roboticsurgical procedure, the surface tracking data may need to be updatedmore frequently or may need to be exceedingly accurate such that thecomputer-implemented program may execute the robotic surgical procedurewith precision and accuracy.

In an embodiment, the system 2500 is configured to generate an occupancygrid map comprising an array of cells divided into grids. The system2500 is configured to store height values for each of the respectivegrid cells to determine a surface mapping of a three-dimensionalenvironment in a light deficient environment.

FIGS. 26A and 26B illustrate a perspective view and a side view,respectively, of an implementation of a monolithic sensor 2600 having aplurality of pixel arrays for producing a three-dimensional image inaccordance with the teachings and principles of the disclosure. Such animplementation may be desirable for three-dimensional image capture,wherein the two-pixel arrays 2602 and 2604 may be offset during use. Inanother implementation, a first pixel array 2602 and a second pixelarray 2604 may be dedicated to receiving a predetermined range of wavelengths of electromagnetic radiation, wherein the first pixel array isdedicated to a different range of wavelength electromagnetic radiationthan the second pixel array.

FIGS. 27A and 27B illustrate a perspective view and a side view,respectively, of an implementation of an imaging sensor 2700 built on aplurality of substrates. As illustrated, a plurality of pixel columns2704 forming the pixel array are located on the first substrate 2702 anda plurality of circuit columns 2708 are located on a second substrate2706. Also illustrated in the figure are the electrical connection andcommunication between one column of pixels to its associated orcorresponding column of circuitry. In one implementation, an imagesensor, which might otherwise be manufactured with its pixel array andsupporting circuitry on a single, monolithic substrate/chip, may havethe pixel array separated from all or a majority of the supportingcircuitry. The disclosure may use at least two substrates/chips, whichwill be stacked together using three-dimensional stacking technology.The first 2702 of the two substrates/chips may be processed using animage CMOS process. The first substrate/chip 2702 may be comprisedeither of a pixel array exclusively or a pixel array surrounded bylimited circuitry. The second or subsequent substrate/chip 2706 may beprocessed using any process and does not have to be from an image CMOSprocess. The second substrate/chip 2706 may be, but is not limited to, ahighly dense digital process to integrate a variety and number offunctions in a very limited space or area on the substrate/chip, or amixed-mode or analog process to integrate for example precise analogfunctions, or a RF process to implement wireless capability, or MEMS(Micro-Electro-Mechanical Systems) to integrate MEMS devices. The imageCMOS substrate/chip 2702 may be stacked with the second or subsequentsubstrate/chip 2706 using any three-dimensional technique. The secondsubstrate/chip 2706 may support most, or a majority, of the circuitrythat would have otherwise been implemented in the first image CMOS chip2702 (if implemented on a monolithic substrate/chip) as peripheralcircuits and therefore have increased the overall system area whilekeeping the pixel array size constant and optimized to the fullestextent possible. The electrical connection between the twosubstrates/chips may be done through interconnects, which may be wirebonds, bump and/or TSV (Through Silicon Via).

FIGS. 28A and 28B illustrate a perspective view and a side view,respectively, of an implementation of an imaging sensor 2800 having aplurality of pixel arrays for producing a three-dimensional image. Thethree-dimensional image sensor may be built on a plurality of substratesand may comprise the plurality of pixel arrays and other associatedcircuitry, wherein a plurality of pixel columns 2802 a forming the firstpixel array and a plurality of pixel columns 2802 b forming a secondpixel array are located on respective substrates 2808 a and 2808 b,respectively, and a plurality of circuit columns 2806 a and 2806 b arelocated on a separate substrate 2804. Also illustrated are theelectrical connections and communications between columns of pixels toassociated or corresponding column of circuitry.

The plurality of pixel arrays may sense information simultaneously andthe information from the plurality of pixel arrays may be combined togenerate a three-dimensional image. In an embodiment, an endoscopicimaging system includes two or more pixel arrays that can be deployed togenerate three-dimensional imaging. The endoscopic imaging system mayinclude an emitter for emitting pulses of electromagnetic radiationduring a blanking period of the pixel arrays. The pixel arrays may besynced such that the optical black pixels are read (i.e., the blankingperiod occurs) at the same time for the two or more pixel arrays. Theemitter may emit pulses of electromagnetic radiation for charging eachof the two or more pixel arrays. The two or more pixel arrays may readtheir respective charged pixels at the same time such that the readoutperiods for the two or more pixel arrays occur at the same time or atapproximately the same time. In an embodiment, the endoscopic imagingsystem includes multiple emitters that are each individual synced withone or more pixel arrays of a plurality of pixel arrays. Informationfrom a plurality of pixel arrays may be combined to generatethree-dimensional image frames and video streams.

It will be appreciated that the teachings and principles of thedisclosure may be used in a reusable device platform, a limited usedevice platform, a re-posable use device platform, or a singleuse/disposable device platform without departing from the scope of thedisclosure. It will be appreciated that in a re-usable device platforman end-user is responsible for cleaning and sterilization of the device.In a limited use device platform, the device can be used for somespecified amount of times before becoming inoperable. Typical new deviceis delivered sterile with additional uses requiring the end-user toclean and sterilize before additional uses. In a re-posable use deviceplatform, a third-party may reprocess the device (e.g., cleans, packagesand sterilizes) a single-use device for additional uses at a lower costthan a new unit. In a single use/disposable device platform a device isprovided sterile to the operating room and used only once before beingdisposed of.

EXAMPLES

The following examples pertain to preferred features of furtherembodiments:

Example 1 is a system. The system includes an emitter for emittingpulses of electromagnetic radiation. The system includes an endoscope.The endoscope comprises an image sensor, and the image sensor comprisesa pixel array for sensing reflected electromagnetic radiation. Thesystem includes a waveguide communicating the pulses of electromagneticradiation from the emitter to the endoscope. The system includes acontroller in electronic communication with the emitter and the imagesensor. The system is such that at least a portion of the pulses ofelectromagnetic radiation emitted by the emitter comprises a lasermapping pattern.

Example 2 is a system as in Example 1, wherein: the emitter comprises aplurality of emitters disposed within an emitter module; the imagesensor is located a distal end of a lumen of the endoscope; and thewaveguide communicates the pulses of electromagnetic radiation from theemitter module to the distal end of the lumen of the endoscope.

Example 3 is a system as in any of Examples 1-2, wherein the waveguidecomprises one of: a single optical fiber; or an optical fiber bundlecomprising a plurality of optical fibers.

Example 4 is a system as in any of Examples 1-3, further comprising alumen of the endoscope comprising a distal end, and wherein the distalend of the lumen is configured for insertion into a light deficientenvironment for optical imaging, and wherein: the waveguide is anoptical fiber bundle comprising a plurality of optical fibers; theplurality of optical fibers are disposed within the lumen and terminateat the distal end of the lumen; and the plurality of optical fibers areaimed in at least two different directions at the distal end of thelumen such that a light cone generated by the pulses of electromagneticradiation exiting the plurality of optical fibers has an increased area.

Example 5 is a system as in any of Examples 1-4, wherein the waveguidecomprises: a first portion comprising a plurality of plastic opticalfibers; a second portion comprising a plurality of glass optical fibers;and a connector for connecting the first portion and the second portionsuch that electromagnetic radiation is communicated from the firstportion to the second portion.

Example 6 is a system as in any of Examples 1-5, wherein the waveguidecomprises an optical diffuser for increasing the area of a light conegenerated by the pulses of electromagnetic radiation exiting thewaveguide.

Example 7 is a system as in any of Examples 1-6, wherein: the emittercomprises a plurality of emitters in an emitter module; the waveguidecomprises a single optical fiber extending from the emitter module to adistal end of a lumen of the endoscope; the single optical fiberreceives the pulses of electromagnetic radiation at the emitter module;and the single optical fiber terminates at the distal end of the lumensuch that the pulses of electromagnetic radiation illuminate a scenelocated at the distal end of the lumen.

Example 8 is a system as in any of Examples 1-7, further comprising alumen of the endoscope, wherein the lumen comprises: an inner cavitydefined by an inner cylinder for receiving optical components of theendoscope; and a peripheral cavity defined by the inner cylinder and anouter cylinder for receiving the waveguide.

Example 9 is a system as in any of Examples 1-8, wherein: the waveguidecomprises an optical fiber bundle comprising a plurality of plasticoptical fibers, wherein the emitter emits the pulses of electromagneticradiation into the optical fiber bundle; the waveguide further comprisesan intervening optical component, wherein the pulses of electromagneticradiation pass through the intervening optical component before enteringthe optical fiber bundle; and the intervening optical componentcomprises a plurality of glass optical fibers.

Example 10 is a system as in any of Examples 1-9, wherein the waveguidecomprises: an optical fiber bundle, wherein the emitter emits the pulsesof electromagnetic radiation into the optical fiber bundle; and adiffuser disposed at a distal end of the optical fiber bundle; whereinthe diffuser provides a light cone having a field of view angle between110 degrees and 120 degrees.

Example 11 is a system as in any of Examples 1-10, wherein the waveguidecomprises: a single optical fiber, wherein the emitter emits the pulsesof electromagnetic radiation into the single optical fiber; and adiffuser disposed at a distal end of the single optical fiber; whereinthe diffuser provides a light cone having a field of view angle between110 degrees and 120 degrees.

Example 12 is a system as in any of Examples 1-11, wherein the pixelarray of the image sensor senses reflected electromagnetic radiation togenerate the plurality of exposure frames during readout periods of thepixel array, wherein the readout period comprises a duration of timewhen active pixels in the pixel array are read, and wherein a singleexposure frame corresponds with a single readout period of the pixelarray.

Example 13 is a system as in any of Examples 1-12, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter is a hyperspectral wavelength for eliciting a spectral response,wherein the hyperspectral wavelength comprises one or more of: theelectromagnetic radiation having the wavelength from about 513 nm toabout 545 nm and the electromagnetic radiation having the wavelengthfrom about 900 nm to about 1000 nm; or the electromagnetic radiationhaving the wavelength from about 565 nm to about 585 nm and theelectromagnetic radiation having the wavelength from about 900 nm toabout 1000 nm.

Example 14 is a system as in any of Examples 1-13, wherein the emitteris configured to emit, during a pulse duration, a plurality ofsub-pulses of electromagnetic radiation having a sub-duration shorterthan the pulse duration.

Example 15 is a system as in any of Examples 1-14, wherein one or moreof the pulses of electromagnetic radiation emitted by the emittercomprises electromagnetic radiation emitted at two or more wavelengthssimultaneously as a single pulse or a single sub-pulse.

Example 16 is a system as in any of Examples 1-15, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter is a hyperspectral emission that results in a hyperspectralexposure frame created by the image sensor, and wherein the controlleris configured to provide the hyperspectral exposure frame to acorresponding hyperspectral system that determines a location of acritical tissue structure within a scene based on the hyperspectralexposure frame.

Example 17 is a system as in any of Examples 1-16, wherein thehyperspectral emission comprises: the electromagnetic radiation havingthe wavelength from about 513 nm to about 545 nm and the electromagneticradiation having the wavelength from about 900 nm to about 1000 nm; orthe electromagnetic radiation having the wavelength from about 565 nm toabout 585 nm and the electromagnetic radiation having the wavelengthfrom about 900 nm to about 1000 nm.

Example 18 is a system as in any of Examples 1-17, wherein thecontroller is further configured to: receive the location of thecritical tissue structure from the corresponding hyperspectral system;generate an overlay frame comprising the location of the critical tissuestructure; and combine the overlay frame with a color image framedepicting the scene to indicate the location of the critical tissuestructure within the scene.

Example 19 is a system as in any of Examples 1-18, wherein sensing thereflected electromagnetic radiation by the pixel array comprisesgenerating a laser mapping exposure frame by sensing reflectedelectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern, and wherein the controller is further configured to:provide the laser mapping exposure frame to a corresponding lasermapping system that determines a topology of the scene and/or dimensionsof one or more objects within the scene; provide the location of thecritical tissue structure to the corresponding laser mapping system; andreceive a topology and/or dimension of the critical tissue structurefrom the corresponding laser mapping system.

Example 20 is a system as in any of Examples 1-19, wherein the criticalstructure comprises one or more of a nerve, a ureter, a blood vessel, anartery, a blood flow, or a tumor.

Example 21 is a system as in any of Examples 1-20, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter is a fluorescence excitation wavelength that results in afluorescence exposure frame created by the image sensor, and wherein thecontroller is configured to provide the fluorescence exposure frame to acorresponding fluorescence system that determines a location of acritical tissue structure within a scene based on the fluorescenceexposure frame.

Example 22 is a system as in any of Examples 1-21, wherein thefluorescence excitation emission comprises one or more of:electromagnetic radiation having a wavelength from about 770 nm to about790 nm; or the electromagnetic radiation having the wavelength fromabout 795 nm to about 815 nm.

Example 23 is a system as in any of Examples 1-22, wherein thecontroller is further configured to: receive the location of thecritical tissue structure from the corresponding fluorescence system;generate an overlay frame comprising the location of the critical tissuestructure; and combine the overlay frame with a color image framedepicting the scene to indicate the location of the critical tissuestructure within the scene.

Example 24 is a system as in any of Examples 1-23, wherein sensing thereflected electromagnetic radiation by the pixel array comprisesgenerating a laser mapping exposure frame by sensing reflectedelectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern, and wherein the controller is further configured to:provide the laser mapping exposure frame to a corresponding lasermapping system that determines a topology of the scene and/or dimensionsof one or more objects within the scene; provide the location of thecritical tissue structure to the corresponding laser mapping system; andreceive a topology and/or dimension of the critical tissue structurefrom the corresponding laser mapping system.

Example 25 is a system as in any of Examples 1-24, wherein the criticalstructure comprises one or more of a nerve, a ureter, a blood vessel, anartery, a blood flow, or a tumor.

Example 26 is a system as in any of Examples 1-25, wherein thecontroller is configured to synchronize timing of the pulses ofelectromagnetic radiation during a blanking period of the image sensor,wherein the blanking period corresponds to a time between a readout of alast row of active pixels in the pixel array and a beginning of a nextsubsequent readout of active pixels in the pixel array.

Example 27 is a system as in any of Examples 1-26, wherein two or morepulses of electromagnetic radiation emitted by the emitter result in twoor more instances of reflected electromagnetic radiation that are sensedby the pixel array to generate two or more exposure frames that arecombined to form an image frame.

Example 28 is a system as in any of Examples 1-27, wherein the imagesensor comprises a first image sensor and a second image sensor suchthat the image sensor can generate a three-dimensional image.

Example 29 is a system as in any of Examples 1-28, wherein the emitteris configured to emit a sequence of pulses of electromagnetic radiationrepeatedly sufficient for generating a video stream comprising aplurality of image frames, wherein each image frame in the video streamcomprises data from a plurality of exposure frames, and wherein each ofthe exposure frames corresponds to a pulse of electromagnetic radiation.

Example 30 is a system as in any of Examples 1-29, wherein the pulses ofelectromagnetic radiation are emitted in a pattern of varyingwavelengths of electromagnetic radiation, and wherein the emitterrepeats the pattern of varying wavelengths of electromagnetic radiation.

Example 31 is a system as in any of Examples 1-30, wherein at least aportion of the pulses of electromagnetic radiation comprise a redwavelength, a green wavelength, a blue wavelength, and a hyperspectralwavelength such that reflected electromagnetic radiation sensed by thepixel array corresponding to each of the red wavelength, the greenwavelength, the blue wavelength, and the hyperspectral wavelength can beprocessed to generate a Red-Green-Blue (RGB) image frame comprising anoverlay of hyperspectral imaging data, wherein the hyperspectralwavelength of electromagnetic radiation comprises: the electromagneticradiation having the wavelength from about 513 nm to about 545 nm andthe electromagnetic radiation having the wavelength from about 900 nm toabout 1000 nm; or the electromagnetic radiation having the wavelengthfrom about 565 nm to about 585 nm and the electromagnetic radiationhaving the wavelength from about 900 nm to about 1000 nm.

Example 32 is a system as in any of Examples 1-31, wherein at least aportion of the pulses of electromagnetic radiation comprise a luminanceemission, a red chrominance emission, a blue chrominance emission, and ahyperspectral emission such that reflected electromagnetic radiationsensed by the pixel array corresponding to each of the luminanceemission, the red chrominance emission, the blue chrominance emission,and the hyperspectral emission can be processed to generate a YCbCrimage frame comprising an overlay of hyperspectral imaging data, whereinthe hyperspectral emission of electromagnetic radiation comprises: theelectromagnetic radiation having the wavelength from about 513 nm toabout 545 nm and the electromagnetic radiation having the wavelengthfrom about 900 nm to about 1000 nm; or the electromagnetic radiationhaving the wavelength from about 565 nm to about 585 nm and theelectromagnetic radiation having the wavelength from about 900 nm toabout 1000 nm.

Example 33 is a system as in any of Examples 1-32, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter is a fluorescence excitation wavelength for fluorescing areagent, wherein the fluorescence excitation wavelength comprises one ormore of: the electromagnetic radiation having the wavelength from about770 nm to about 790 nm; or the electromagnetic radiation having thewavelength from about 795 nm to about 815 nm.

Example 34 is a system as in any of Examples 1-33, wherein at least aportion of the pulses of electromagnetic radiation comprise a redwavelength, a green wavelength, a blue wavelength, and a fluorescenceexcitation wavelength such that reflected electromagnetic radiationsensed by the pixel array corresponding to each of the red wavelength,the green wavelength, the blue wavelength, and the fluorescenceexcitation wavelength can be processed to generate a Red-Green-Blue(RGB) image frame comprising an overlay of fluorescence imaging data,wherein the fluorescence wavelength of electromagnetic radiationcomprises: electromagnetic radiation having the wavelength from about770 nm to about 790 nm and/or electromagnetic radiation having thewavelength from about 795 nm to about 815 nm.

Example 35 is a system as in any of Examples 1-34, wherein at least aportion of the pulses of electromagnetic radiation comprise a luminanceemission, a red chrominance emission, a blue chrominance emission, and afluorescence excitation emission such that reflected electromagneticradiation sensed by the pixel array corresponding to each of theluminance emission, the red chrominance emission, the blue chrominanceemission, and the fluorescence excitation emission can be processed togenerate a YCbCr image frame comprising an overlay of fluorescenceimaging data, wherein the fluorescence wavelength of electromagneticradiation comprises: electromagnetic radiation having the wavelengthfrom about 770 nm to about 790 nm and/or electromagnetic radiationhaving the wavelength from about 795 nm to about 815 nm.

Example 36 is a system as in any of Examples 1-35, wherein the waveguidecomprises a single optical fiber, wherein the emitter emits the pulsesof electromagnetic radiation into the single optical fiber.

Example 37 is a system as in any of Examples 1-36, wherein the pixelarray is a two-dimensional array of independent pixels each capable ofdetecting any wavelength of electromagnetic radiation.

Example 38 is a system as in any of Examples 1-37, further comprising afilter that filters electromagnetic radiation having a wavelength fromabout 770 nm to about 790 nm.

Example 39 is a system as in any of Examples 1-38, further comprising afilter that filters electromagnetic radiation having a wavelength fromabout 795 nm to about 815 nm.

Example 40 is a system as in any of Examples 1-39, wherein the imagesensor is CMOS image sensor.

Example 41 is a system as in any of Examples 1-40, wherein sensingreflected electromagnetic radiation by the pixel array comprisesgenerating a laser mapping exposure frame by sensing reflectedelectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern, wherein the laser mapping exposure frame comprisesinformation for determining real time measurements comprising one ormore of: a distance from an endoscope to an object; an angle between anendoscope and the object; or surface topology information about theobject.

Example 42 is a system as in any of Examples 1-41, wherein the lasermapping exposure frame comprises information for determining the realtime measurements to an accuracy of less than 10 centimeters.

Example 43 is a system as in any of Examples 1-42, wherein the lasermapping exposure frame comprises information for determining the realtime measurements to an accuracy of less than one millimeter.

Example 44 is a system as in any of Examples 1-43, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter comprises a plurality of tool-specific laser mapping patternsfor each of a plurality of tools within a scene.

Example 45 is a system as in any of Examples 1-44, wherein the lasermapping pattern emitted by the emitter comprises a first output and asecond output that are independent from one another, wherein the firstoutput is for light illumination and the second output is for tooltracking.

Example 46 is a system as in any of Examples 1-45, wherein the emitteris an emitter module comprising a first emitter and a second emitter,and wherein the first emitter comprises a plurality of lasers foremitting pulses of a first wavelength of electromagnetic radiation andthe second emitter comprises a plurality of lasers for emitting pulsesof a second wavelength of electromagnetic radiation.

Example 47 is a system as in any of Examples 1-46, wherein the imagesensor is configured to generate a plurality of exposure frames, whereineach of the plurality of exposure frames corresponds to one or morepulses of electromagnetic radiation emitted by the emitter.

Example 48 is a system as in any of Examples 1-47, wherein the waveguidecomprises an optical fiber bundle comprising between 2 and 150 fibers.

Example 49 is a system as in any of Examples 1-48, wherein the emittercomprises a third emitter comprising a plurality of lasers for emittingpulses of a third wavelength of electromagnetic radiation.

Example 50 is a system as in any of Examples 1-49, wherein the emittercomprises a fourth emitter comprising a plurality of lasers for emittingpulses of a fourth wavelength of electromagnetic radiation.

Example 51 is a system as in any of Examples 1-50, wherein the emittercomprises one or more hyperspectral emitters for emitting pulses ofhyperspectral wavelengths of electromagnetic radiation for eliciting aspectral response.

Example 52 is a system as in any of Examples 1-51, wherein each of theone or more hyperspectral emitters comprises an emitter comprising aplurality of lasers.

Example 53 is a system as in any of Examples 1-52, wherein the emitterfurther comprises an optical element for mixing pulses ofelectromagnetic radiation before entry into the waveguide, wherein theoptical element comprises one or more of a diffuser, a mixing rod, or alens.

Example 54 is a system as in any of Examples 1-53, further comprising adichroic mirror for reflecting blue wavelengths of electromagneticradiation.

Example 55 is a system as in any of Examples 1-54, further comprising adichroic mirror for reflecting green wavelengths of electromagneticradiation.

Example 56 is a system as in any of Examples 1-55, further comprising adichroic mirror for reflecting red wavelengths of electromagneticradiation.

Example 57 is a system as in any of Examples 1-56, further comprising adichroic mirror for reflecting electromagnetic radiation having awavelength from about 513 nm to about 545 nm.

Example 58 is a system as in any of Examples 1-57, further comprising adichroic mirror for reflecting electromagnetic radiation having awavelength from about 565 nm to about 585 nm.

Example 59 is a system as in any of Examples 1-58, further comprising adichroic mirror for reflecting electromagnetic radiation having awavelength from about 900 nm to about 1000 nm.

Example 60 is a system as in any of Examples 1-59, further comprising adichroic mirror for reflecting electromagnetic radiation having awavelength from about 770 nm to about 790 nm.

Example 61 is a system as in any of Examples 1-60, further comprising adichroic mirror for reflecting electromagnetic radiation having awavelength from about 795 nm to about 815 nm.

Example 62 is a system as in any of Examples 1-61, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainband of wavelengths, wherein the dichroic mirror is transparent toelectromagnetic radiation of other wavelengths.

Example 63 is a system as in any of Examples 1-62, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a red wavelength.

Example 64 is a system as in any of Examples 1-63, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a green wavelength.

Example 65 is a system as in any of Examples 1-64, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a blue wavelength.

Example 66 is a system as in any of Examples 1-65, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a wavelength from about 513 nm to about545 nm.

Example 67 is a system as in any of Examples 1-66, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a wavelength from about 565 nm to about585 nm.

Example 68 is a system as in any of Examples 1-67, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a wavelength from about 900 nm to about1000 nm.

Example 69 is a system as in any of Examples 1-68, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a wavelength from about 770 nm to about790 nm.

Example 70 is a system as in any of Examples 1-69, further comprising adichroic mirror for reflecting electromagnetic radiation of a certainwavelength, wherein the dichroic mirror is transparent at least toelectromagnetic radiation having a wavelength from about 795 nm to about815 nm.

Example 71 is a system as in any of Examples 1-70, wherein the emittercomprises a plurality of laser emitters, and wherein the plurality oflaser emitters have Gaussian cross-sectional intensity profiles.

Example 72 is a system as in any of Examples 1-71, wherein the emittercomprises a plurality of laser emitters, and wherein the plurality oflaser emitter have a flat or approximately flat shaped intensityprofile.

Example 73 is a system as in any of Examples 1-72, wherein the emittercomprises a plurality of laser emitters, and wherein the plurality oflaser emitters have a top hat shaped intensity profile.

Example 74 is a system as in any of Examples 1-73, wherein the firstemitter and the second emitter are aimed at a collection region suchthat the pulses of the first wavelength of electromagnetic radiation andthe pulses of the second wavelength of electromagnetic radiation mix atthe collection region and are received by the waveguide.

Example 75 is a system as in any of Examples 1-74, further comprising anintervening optical element disposed between the emitter and thewaveguide, wherein the intervening optical element is configured to mixemissions from the first emitter and the second emitter prior to theemission reaching the waveguide.

Example 76 is a system as in any of Examples 1-75, further comprising anintervening optical element disposed between the emitter and thewaveguide configured to homogenously mix independent emissions ofelectromagnetic radiation from the first emitter and the second emitterprior to reaching the waveguide.

It will be appreciated that various features disclosed herein providesignificant advantages and advancements in the art. The following claimsare exemplary of some of those features.

In the foregoing Detailed Description of the Disclosure, variousfeatures of the disclosure are grouped together in a single embodimentfor the purpose of streamlining the disclosure. This method ofdisclosure is not to be interpreted as reflecting an intention that theclaimed disclosure requires more features than are expressly recited ineach claim. Rather, inventive aspects lie in less than all features of asingle foregoing disclosed embodiment.

It is to be understood that any features of the above-describedarrangements, examples, and embodiments may be combined in a singleembodiment comprising a combination of features taken from any of thedisclosed arrangements, examples, and embodiments.

It is to be understood that the above-described arrangements are onlyillustrative of the application of the principles of the disclosure.Numerous modifications and alternative arrangements may be devised bythose skilled in the art without departing from the spirit and scope ofthe disclosure and the appended claims are intended to cover suchmodifications and arrangements.

Thus, while the disclosure has been shown in the drawings and describedabove with particularity and detail, it will be apparent to those ofordinary skill in the art that numerous modifications, including, butnot limited to, variations in size, materials, shape, form, function andmanner of operation, assembly and use may be made without departing fromthe principles and concepts set forth herein.

Further, where appropriate, functions described herein can be performedin one or more of: hardware, software, firmware, digital components, oranalog components. For example, one or more application specificintegrated circuits (ASICs) or field programmable gate arrays (FPGAs)can be programmed to carry out one or more of the systems and proceduresdescribed herein. Certain terms are used throughout the followingdescription and claims to refer to particular system components. As oneskilled in the art will appreciate, components may be referred to bydifferent names. This document does not intend to distinguish betweencomponents that differ in name, but not function.

The foregoing description has been presented for the purposes ofillustration and description. It is not intended to be exhaustive or tolimit the disclosure to the precise form disclosed. Many modificationsand variations are possible in light of the above teaching. Further, itshould be noted that any or all the aforementioned alternateimplementations may be used in any combination desired to formadditional hybrid implementations of the disclosure.

Further, although specific implementations of the disclosure have beendescribed and illustrated, the disclosure is not to be limited to thespecific forms or arrangements of parts so described and illustrated.The scope of the disclosure is to be defined by the claims appendedhereto, any future claims submitted here and in different applications,and their equivalents.

What is claimed is:
 1. A system comprising: an emitter for emittingpulses of electromagnetic radiation; an endoscope comprising an imagesensor, wherein the image sensor comprises a pixel array for sensingreflected electromagnetic radiation; a waveguide for communicating thepulses of electromagnetic radiation from the emitter to the endoscope;and a controller in electronic communication with the emitter and theimage sensor; wherein at least a portion of the pulses ofelectromagnetic radiation emitted by the emitter comprises a lasermapping pattern; wherein the pixel array of the image sensor senseselectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern; wherein a laser mapping exposure frame is generatedfrom data resulting from the emitter pulsing the laser mapping pattern;and wherein the system provides the laser mapping exposure frame to acorresponding system.
 2. The system of claim 1, wherein: the emittercomprises a plurality of emitters disposed within an emitter module; theimage sensor is located a distal end of a lumen of the endoscope; andthe waveguide communicates the pulses of electromagnetic radiation fromthe emitter module to the distal end of the lumen of the endoscope. 3.The system of claim 1, wherein the waveguide comprises one of: a singleoptical fiber; or an optical fiber bundle comprising a plurality ofoptical fibers.
 4. The system of claim 1, further comprising a lumen ofthe endoscope comprising a distal end, and wherein the distal end of thelumen is configured for insertion into a light deficient environment foroptical imaging, and wherein: the waveguide is an optical fiber bundlecomprising a plurality of optical fibers; the plurality of opticalfibers are disposed within the lumen and terminate at the distal end ofthe lumen; and the plurality of optical fibers are aimed in at least twodifferent directions at the distal end of the lumen such that a lightcone generated by the pulses of electromagnetic radiation exiting theplurality of optical fibers has an increased area.
 5. The system ofclaim 1, wherein the waveguide comprises: a first portion comprising aplurality of plastic optical fibers; a second portion comprising aplurality of glass optical fibers; and a connector for connecting thefirst portion and the second portion such that electromagnetic radiationis communicated from the first portion to the second portion.
 6. Thesystem of claim 1, wherein the waveguide comprises an optical diffuserfor increasing the area of a light cone generated by the pulses ofelectromagnetic radiation exiting the waveguide.
 7. The system of claim1, wherein: the emitter comprises a plurality of emitters in an emittermodule; the waveguide comprises a single optical fiber extending fromthe emitter module to a distal end of a lumen of the endoscope; thesingle optical fiber receives the pulses of electromagnetic radiation atthe emitter module; and the single optical fiber terminates at thedistal end of the lumen such that the pulses of electromagneticradiation illuminate a scene located at the distal end of the lumen. 8.The system of claim 1, further comprising a lumen of the endoscope,wherein the lumen comprises: an inner cavity defined by an innercylinder for receiving optical components of the endoscope; and aperipheral cavity defined by the inner cylinder and an outer cylinderfor receiving the waveguide.
 9. The system of claim 1, wherein: thewaveguide comprises an optical fiber bundle comprising a plurality ofplastic optical fibers, wherein the emitter emits the pulses ofelectromagnetic radiation into the optical fiber bundle; the waveguidefurther comprises an intervening optical component, wherein the pulsesof electromagnetic radiation pass through the intervening opticalcomponent before entering the optical fiber bundle; and the interveningoptical component comprises a plurality of glass optical fibers.
 10. Thesystem of claim 1, wherein the waveguide comprises: an optical fiberbundle, wherein the emitter emits the pulses of electromagneticradiation into the optical fiber bundle; and a diffuser disposed at adistal end of the optical fiber bundle; wherein the diffuser provides alight cone having a field of view angle between 110 degrees and 120degrees.
 11. The system of claim 1, wherein the waveguide comprises: asingle optical fiber, wherein the emitter emits the pulses ofelectromagnetic radiation into the single optical fiber; and a diffuserdisposed at a distal end of the single optical fiber; wherein thediffuser provides a light cone having a field of view angle between 110degrees and 120 degrees.
 12. The system of claim 1, wherein the imagesensor is configured to generate a plurality of exposure frames, whereineach of the plurality of exposure frames corresponds to one or morepulses of electromagnetic radiation emitted by the emitter.
 13. Thesystem of claim 12, wherein the pixel array of the image sensor sensesreflected electromagnetic radiation to generate the plurality ofexposure frames during readout periods of the pixel array, wherein areadout period comprises a duration of time when active pixels in thepixel array are read, and wherein a single exposure frame correspondswith a single readout period of the pixel array.
 14. The system of claim1, wherein the emitter is configured to emit, during a pulse duration, aplurality of sub-pulses of electromagnetic radiation having asub-duration shorter than the pulse duration.
 15. The system of claim 1,wherein one or more of the pulses of electromagnetic radiation emittedby the emitter comprises electromagnetic radiation emitted at two ormore wavelengths simultaneously as a single pulse or a single sub-pulse.16. The system of claim 1, wherein at least a portion of the pulses ofelectromagnetic radiation emitted by the emitter is a fluorescenceexcitation emission that results in a fluorescence exposure framecreated by the image sensor, and wherein the controller is configured toprovide the fluorescence exposure frame to a corresponding fluorescencesystem that determines a location of a critical tissue structure withina scene based on the fluorescence exposure frame.
 17. The system ofclaim 16, wherein the fluorescence excitation emission comprises one ormore of: electromagnetic radiation having a wavelength from about 770 nmto about 790 nm; or electromagnetic radiation having the wavelength fromabout 795 nm to about 815 nm.
 18. The system of claim 17, wherein thecontroller is further configured to: receive the location of thecritical tissue structure from the corresponding fluorescence system;generate an overlay frame comprising the location of the critical tissuestructure; and combine the overlay frame with a color image framedepicting the scene to indicate the location of the critical tissuestructure within the scene.
 19. The system of claim 18, wherein sensingthe reflected electromagnetic radiation by the pixel array comprisesgenerating a laser mapping exposure frame by sensing reflectedelectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern, and wherein the controller is configured to: providethe laser mapping exposure frame to a corresponding laser mapping systemthat determines a topology of the scene and/or dimensions of one or moreobjects within the scene; provide the location of the critical tissuestructure to the corresponding laser mapping system; and receive atopology and/or dimension of the critical tissue structure from thecorresponding laser mapping system.
 20. The system of claim 19, whereinthe critical structure comprises one or more of a nerve, a ureter, ablood vessel, an artery, a blood flow, or a tumor.
 21. The system ofclaim 1, wherein the controller is configured to synchronize timing ofthe pulses of electromagnetic radiation during a blanking period of theimage sensor, wherein the blanking period corresponds to a time betweena readout of a last row of active pixels in the pixel array and abeginning of a next subsequent readout of active pixels in the pixelarray.
 22. The system of claim 1, wherein two or more pulses ofelectromagnetic radiation emitted by the emitter result in two or moreinstances of reflected electromagnetic radiation that are sensed by thepixel array to generate two or more exposure frames that are combined toform an image frame.
 23. The system of claim 1, wherein the emitter isconfigured to emit a sequence of pulses of electromagnetic radiationrepeatedly sufficient for generating a video stream comprising aplurality of image frames, wherein each image frame in the video streamcomprises data from a plurality of exposure frames, and wherein each ofthe exposure frames corresponds to one or more pulses of electromagneticradiation.
 24. The system of claim 1, wherein the pulses ofelectromagnetic radiation are emitted in a pattern of varyingwavelengths of electromagnetic radiation, and wherein the emitterrepeats the pattern of varying wavelengths of electromagnetic radiation.25. The system of claim 1, wherein at least a portion of the pulses ofelectromagnetic radiation comprise a red emission, a green emission, ablue emission, and a laser mapping emission such that reflectedelectromagnetic radiation sensed by the pixel array corresponding toeach of the red emission, the green emission, the blue emission, and thelaser mapping emission can be processed to generate a color RGB imageframe comprising an overlay of laser mapping data.
 26. The system ofclaim 1, wherein at least a portion of the pulses of electromagneticradiation comprise a luminance emission, a red chrominance emission, ablue chrominance emission, and a laser mapping emission such thatreflected electromagnetic radiation sensed by the pixel arraycorresponding to each of the luminance emission, the red chrominanceemission, the blue chrominance emission, and the laser mapping emissioncan be processed to generate a YCbCr image frame comprising an overlayof laser mapping data.
 27. The system of claim 1, wherein sensingreflected electromagnetic radiation by the pixel array comprisesgenerating a laser mapping exposure frame by sensing reflectedelectromagnetic radiation resulting from the emitter pulsing the lasermapping pattern, wherein the laser mapping exposure frame comprisesinformation for determining real time measurements comprising one ormore of: a distance from an endoscope to an object; an angle between anendoscope and the object; or surface topology information about theobject.
 28. The system of claim 27, wherein the laser mapping exposureframe comprises information for determining the real time measurementsto an accuracy of less than 10 centimeters.
 29. The system of claim 27,wherein the laser mapping exposure frame comprises information fordetermining the real time measurements to an accuracy of less than onemillimeter.
 30. The system of claim 1, wherein at least a portion of thepulses of electromagnetic radiation emitted by the emitter comprises aplurality of tool-specific laser mapping patterns for each of aplurality of tools within a scene.
 31. The system of claim 1, whereinthe laser mapping pattern emitted by the emitter comprises a firstoutput and a second output that are independent from one another,wherein the first output is for light illumination and the second outputis for tool tracking.
 32. The system of claim 1, wherein at least aportion of the pulses of electromagnetic radiation emitted by theemitter is a hyperspectral emission that results in a hyperspectralexposure frame created by the image sensor, and wherein the controlleris configured to provide the hyperspectral exposure frame to acorresponding hyperspectral system that determines a location of acritical tissue structure within a scene based on the hyperspectralexposure frame.
 33. The system of claim 32, wherein the hyperspectralemission comprises: electromagnetic radiation having the wavelength fromabout 513 nm to about 545 nm and electromagnetic radiation having thewavelength from about 900 nm to about 1000 nm; or electromagneticradiation having the wavelength from about 565 nm to about 585 nm andelectromagnetic radiation having the wavelength from about 900 nm toabout 1000 nm.
 34. The system of claim 33, wherein the controller isfurther configured to: receive the location of the critical tissuestructure from the corresponding hyperspectral system; generate anoverlay frame comprising the location of the critical tissue structure;and combine the overlay frame with a color image frame depicting thescene to indicate the location of the critical tissue structure withinthe scene.
 35. The system of claim 34, wherein sensing the reflectedelectromagnetic radiation by the pixel array comprises generating alaser mapping exposure frame by sensing reflected electromagneticradiation resulting from the emitter pulsing the laser mapping pattern,and wherein the controller is further configured to: provide the lasermapping exposure frame to a corresponding laser mapping system thatdetermines a topology of the scene and/or dimensions of one or moreobjects within the scene; provide the location of the critical tissuestructure to the corresponding laser mapping system; and receive atopology and/or dimension of the critical tissue structure from thecorresponding laser mapping system.
 36. The system of claim 35, whereinthe critical structure comprises one or more of a nerve, a ureter, ablood vessel, an artery, a blood flow, or a tumor.